Pathway In Rats Research Articles

Ferulic acid relieved ulcerative colitis by inhibiting the TXNIP/NLRP3 pathway in rats.

Ulcerative colitis (UC) is a disorder of the bowel that is characterized by a chronic inflammatory response. The traditional Chinese herbal medicine ferulic acid (FA) is known for its antioxidant, antiapoptotic, and antiinflammatory properties. However, its role in UC is still unclear. Thus, the current study was conducted to investigate the role of FA in UC. Rats were treated with 2,4,6-triabrobenzene sulfonic acid to induce UC and subjected to FA. Human intestinal microvascular endothelial cells (HIMECs) were treated with tumor necrosis factor-α (TNF-α) and pretreated with FA. Pathological changes in colonic tissues were visualized via hematoxylin-eosin staining. Enzyme linked immunosorbent assay was conducted to detect interleukin (IL)-6, IL-12, and IL-1β levels. Cell morphology was visualized by using a microscope, and viability was detected by using MTT. The percentage of apoptosis was detected via flow cytometry. Western blot analysis was performed to detect the expression of the apoptosis-related proteins thioredoxin-interacting protein (TXNIP) and NOD-like receptor pyrin domain-containing 3 (NLRP3). In vivo FA administration alleviated intestinal injury in UC rats and inhibited inflammatory factor levels (IL-6, IL-12, and IL-1β), apoptosis-related protein expression (caspase-1 and caspase-3) and the TXNIP/NLRP3 signaling pathway. In vitro, TNF-α treatment reduced HIMEC viability, increased cell apoptosis and inflammatory factor levels and activated the TXNIP/NLRP3 signaling pathway. However, FA treatment restored the viability of HIMECs, reduced TNF-α-induced cell apoptosis and inflammation and inhibited the TXNIP/NLRP3 signaling pathway. Furthermore, with increasing FA concentration, the effects were stronger. In summary, FA inhibits the inflammatory injury of endothelial cells in ulcerative colitis or alleviates TNF-α-induced HIMEC injury by inhibiting the TXNIP/NLRP3 signaling pathway.

Studies on the mechanism of energy metabolism via AMPK/PGC-1α signaling pathway induced by compatibility of Ligusticum chuanxiong Hort and Gastrodia.

AMP-activated protein kinase (AMPK) regulates overall energy consumption and energy intake through cytokines. Ligusticum striatum DC (CX) combined with Gastrodia elata Blume (TM) has been used for migraine treatment for millennia. When used alone in clinical practice, CX causes symptoms of thirst, irritability, and yellow urine and has influenced the levels of cytokines such as AMP that activate the AMPK pathway of energy metabolism. However, relationships between this compatibility prescription, integral biological energy metabolism, and the AMPK pathway remain unclear. Studies were performed by treating normal rats with physiological saline, CX extract, CX coupled TM extract, and TM extracts separately for 4 weeks. Food intake, water intake, urine output, stool output, and body weight were monitored once a week by the metabolic cage method. Values of FBG, BUN, TP, TC and TG in blood samples were detected approaching the whole blood automatic detector from 1 to 4 weeks. Na+-K+-ATPase, Ca2+-Mg2+-ATPase, cAMP, and cGMP activity were determined by the enzyme-linked immunosorbent assay (ELISA); the biological samples that were obtained at 1, 2, 3, and 4 weeks after drug administration were tested by GC-TOF-MS. Then real-time PCR and Western Blot were applied to detect changes in expression of some substances involved in energy metabolism. The results demonstrated that administering CX alone increased energy input, mobility, and respiratory exchange ratio, accelerated energy consumption, and caused inflammatory infiltration in the liver. CX coupled with TM led to lower energy metabolism and liver damage in comparison with CX used alone. Moreover, CX-treated rats harbored higher levels of differential metabolites (including pyrophosphate, oxaloacetic acid, and galactinol). Glycerophospholipid metabolism and the citrate cycle are closely related to the differential metabolites above. In addition, CX-induced unbalanced energy metabolism depends on cAMP activation mediated by the AMPK/PGC-1α pathway in rats. Our findings suggest that CX-induced energy metabolism imbalance was corrected after coupling with TM by mediating the AMPK/PGC-1α pathway.

CHRONIC THIACLOPRID EXPOSURE IMPAIRS COGNITIVE FUNCTION AND TRIGGERS MITOCHONDRIAL APOPTOSIS PATHWAY IN RAT STRIATUM AND HIPPOCAMPUS: NEUROPREVENTIVE EFFECT OF BITTER APRICOT KERNELS EXTRACT (PRUNUS ARMENIACA L.)

Thiacloprid (THI) is a nicotinic receptor agonist widely used as pesticide in Algeria, however it is susceptible to accumulate in various fruits and vegetables and pouring downstream into food plates and contributes to the development of neurodegenerative diseases. Conversely, several natural compounds are provided with cytoprotective potential and, therefore, are able to act against the harmful effects of toxicants such as pesticides. This study focused on striatum (str) and hippocampus (hipp) mitochondrial toxicity assessment, evaluation of behavioral function and intrinsic apoptosis pathway in rats exposed to THI at low-dose (0.020 mg/kg) for 3 months. In addition, this study examined neuroprotective potential of bitter apricot kernel extract when administered concomitantly with THI at the dose of 50 mg/kg. In current study, assessment of mitochondrial permeability transition pore (mPTP) and swelling, evaluation of mitochondrial redox status, cholinergic function (Ach E) and apoptosis markers (Caspase 9 and 3, Bax and Bcl2, Cytochrome c and cytosolic calcium) were performed in both brain areas, besides behavioral and histopathological examination. The results showed an increase of lipid peroxidation in both of str and hipp with a values of 1,14 ± 0,04 nmol/mg of proteins (pr) and 1,58 ± 0,09 nmol/mg pr. respectively and a significant decrease in GSH (0,09 ± 0,01 mmol/mg pr. in hipp and 0,08±0,01 mmol/mg pr. in str), the results also showed a change in the activity of antioxidants enzymes SOD (16,37±1,09 UI/mg pr. in hipp14,54±1,46 UI/mg pr. in str) , CAT (0,010±0,01 UI/mg pr. in hipp and 0,005±0,004 UI/mg pr. in str), GPx (0,01± 0,001 nmol/mg pr. in both hipp and str) and GST (23,73±1,68 UI/mg pr. in hipp and 17,56± 1,04 UI/mg pr. in str), as well as an abrupt increase in mPTP opening with a value of (0,057±0,005 in str and 0,054±0,005 in hipp) , which leaded to mitochondrial swelling where the level o mitochondrial swelling was (0,016±0,002 in str and 0,106±0,003 in hipp), the swelling was associated also with a high releasing of Cyt-c with a values of (4,48 ± 1,26 µg/ml in str and 5,32 ± 1,08 µg/ml in hipp ) and Ca++( 2,26±0,06 mmol/l in str and 2,32±0,07 mmol/l in hipp) into the cytosol, the results also showed a significant decreasing of Bcl2 (16,4 ± 1,86 ng/mg pr in str and 14,8± 0,82 ng/mg pr in hipp), in the other hand the rates of caspase-9 were (278±14 mAbs/mg pr.) in str and 212 ±24 mAbs/mg pr. in hipp), caspase3 (184± 16mAbs/mg pr.) in str and 250 ±14mAbs/mg pr. in hipp), and BAX (0,926 ng/mg pr in str and 1,189 ng/mg pr in hipp) were increased. The results of this study revealed also a decrease of memorization processes and learning abilities, at the same time a decrease in Ach E activity (14,02± 0,78 nmol/min/mg pr. in str and 22,35± 1,77 nmol/min/mg pr. in hipp) was recorded. Inversely, bitter apricot kernels extract showed higher cytoprotective potential against THI neurotoxicity, since mitochondrial redox homeostasis and membrane integrity were recovered, cognitive impairment and brain tissue damage were also prevented. In conclusion, THI induced mitochondrial disorders, triggered apoptosis signaling pathway and impaired cognitive functions which were prevented by bitter apricot kernels extract when associated with this pesticide.

Resveratrol alleviates bleomycin-induced pulmonary fibrosis by inhibiting epithelial-mesenchymal transition and down-regulating TLR4/NF-κB and TGF-β1/smad3 signalling pathways in rats

BackgroundPulmonary fibrosis (PF) is a difficult clinical condition with no effective treatment and a high mortality rate. Patients usually die of respiratory failure. In the present, we hypothesized that resveratrol (Res) could suppress bleomycin (BLM)-induced PF in rats and examined the detailed mechanism. MethodsThe successfully established BLM-induced PF rat models and normal healthy rats were randomly assigned into the control, model, Res-low, Res-medium, and Res-high groups. The extent of PF in rats was determined by Masson and H&E staining. ELISA was used to detect changes in the inflammatory factors IL-1β, IL-6, TNF-α, SOD, and GSH-PX in lung tissue. Microscopic lung fibrosis scoring was done using the Ashcroft scale. Western blotting and RT-qPCR assays were used to analyze the effects of Res on the epithelial-mesenchymal transition (EMT). ResultsThe administration of Res ameliorated the BLM-induced PF in vivo. Res could inhibit pro-inflammatory factors and regulates oxidative stress levels. It also revealed that Res downregulated Vimentin and upregulated E-cadherin expression. Res inhibited fibrosis and inflammatory responses in rat lung tissue. The activation of the TLR4/NF-κB and TGF-β1/smad3 signaling pathways were inhibited following Res treatment. ConclusionThe present study suggested that Res may protect against BLM-induced PF by inhibiting the EMT and down-regulating the TLR4/NF-κB and TGF-β1/smad3 signaling pathways.

Protective effect and mechanism of electroacupuncture of "Biao-Ben" acupoints combination for mitochondrial dysfunction in diabetic nephropathy rats

To study the protective effect of electroacupuncture (EA) at "Biao"-acupoints, "Fenglong"(ST40) and "Zhongwan"(CV12), used for treating symptoms of the disease, and "Ben"-acupoints, "Zusanli"(ST36) and "Guanyuan"(CV4), for treating the root cause of the disease on oxidative stress injury of renal mitochondria through SIRT1/PGC-1α signal pathway in rats with diabetic nephropathy (DN). A total of 33 male Wistar rats were randomized into normal (n=10), model (n=12) and EA (n=11) groups.The DN model was established by feeding the rats with high-sugar and high-fat diet for 6 weeks combined with streptozotocin (STZ, 35 mg/kg, i.p.). EA (4 Hz/60 Hz, 1 mA)was applied to ST36-ST40 and CV4-CV12 for 15 min, once every other day for 8 weeks. The rats' body weight was recorded, urine in 24 hours (24-h UP) was collected to measure the urine protein level, and the fasting blood glucose (FBG) level detected by using a glucometer. The levels of serum glycosylated hemoglobin (HbA1c), creatinine (Scr) and urea nitrogen (BUN) were assayed using immunoturbidi-metry, picric acid method and urease method, respectively, and those of serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) detected using an automatic biochemical analyzer. The kidney tissue was collected for assaying the activity of superoxide dismutase (SOD) with xanthine oxidase method, glutathione (GSH) activity with dithio-dinitrobenzoic acid method, catalase （CAT） activity with ammonium molybdate spectrometric method, and malondialdehyde (MDA) content with thiobarbituric acid method. Histopathological changes of the kidney tissue were observed by microscope after hematoxylin-eosin staining (HE), periodate Schiff staining (PAS) and Masson staining, separately, and its subcellular structure was observed under transmission electron microscopy. The expression levels of renal SIRT1 and PGC-1α mRNAs and proteins were detected by quantitative real-time PCR and Western blot, and the immunoactivity of renal α-smooth muscle actin (α-SMA), and immunofluorescence density of renal collagen Ⅰ (Col Ⅰ), collagen Ⅳ(Col Ⅳ) and fibronec-tin (FN) detected by immunohistochemistry and immunofluorescence assay, respectively. Compared with the normal group, the levels of FBG, HbA1c, BUN, Scr, 24-h UP, TG, TC, LDL-C, MDA, α-SMA, Col Ⅰ, Col Ⅳ and FN proteins were significantly increased (P<0.01), and the levels of body weight, HDL-C, SOD, GSH, CAT, SIRT1 and PGC-1α mRNAs and proteins were decreased in the model group (P<0.01, P<0.05). In comparison with the model group, the levels of FBG, HbA1c, BUN, Scr, 24-h UP, TG, TC, LDL-C and MDA, and the expressions of α-SMA, Col Ⅰ, Col Ⅳ and FN proteins were markedly down-regulated (P<0.05, P<0.01), and those of body weight, HDL-C, SOD, GSH, CAT, and the expressions of SIRT1 and PGC-1α mRNAs and proteins significantly up-regulated (P<0.01, P<0.05) in the EA group. HE staining showed mesangial dilatation, glomerular hypertrophy and mesangial matrix accumulation; PAS staining showed an increase of the glomerular extracellular matrix deposition; and Masson staining displayed an enhancement of glomerular fibrosis and interstitial space expansion; and electron microscope revealed foot process fusion, basement membrane thickening and organelle injury in the rat's kidney of the model group, which were relatively milder in the EA group. EA of ST36-ST40 and CV4-CV12, "Biao-Ben" acupoints combination, can alleviate oxidative stress and mitochondrial dysfunction in DN rats, which may be associated with its functions in up-regulating SIRT1/PGC-1α signaling, and decreasing renal fibrosis.

Involvement of miR-126-3p via mTOR/HIF-1α signaling pathway in effect of electroacupuncture on angiogenesis in rats with cerebral ischemia

To observe the effect of electroacupuncture (EA) on miRNA-126-3p and mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) signaling pathway in rats with cerebral ischemia (CI), so as to explore the underlying mechanism of EA on angiogenesis. Male SD rats were randomly divided into control group, model group, EA group and EA+inhibitor group (inhibitor group), which were further divided into 3, 7 and 14 d subgroups, with 12 rats in each sub-group. The CI model was established by occlusion of the middle cerebral artery. EA (2 Hz/20 Hz, 0.5 mA) was applied to "Dazhui" (GV14), "Baihui" (GV20) for 20 min, once daily for 14 days at most. Rats of the inhibitor group were given an intraperitoneally injection of mTOR inhibitor (0.1 mg/mL, 0.3 mg/kg) before daily EA. The neurological function was evaluated by modified neurological severity score (mNSS). The ultrastructure of cortical neurons and microvascular endothelial cells in ischemic penumbra was observed by transmission electron microscope, and the microvessel density (MVD) of cortical endothelium in ischemic penumbra was detected by immunohistochemistry. Western blot and quantitative real-time PCR were used to detect the protein and mRNA expression of mTOR, HIF-1α and the expression of miR-126-3p in the cortex of ischemic penumbra, respectively. After modeling, compared with the control group at the same time point, the mNSS of the model group was increased (P<0.01), and decreased over time (P<0.01). The cortical neurons and brain microvascular endothelial cells in the ischemic penumbra were edema, and the cell structure was damaged obviously in the model group.The MVD value and the expressions of mTOR、HIF-1α proteins and mRNAs were increased (P<0.01), while the expression of miR-126-3p decreased (P<0.01) in the model group relative to the control group. Compared with the model group at the same time point, the mNSS of both intervention groups was significantly reduced (P<0.01, P<0.05), the neuron and cerebral microvascular structure improved to varying degrees, and the MVD value, the expressions of mTOR and HIF-1α protein and mRNA, and the expression of miR-126-3p of the two treatment groups were increased (P<0.01, P<0.05) at all time points (excep MVD at day 7 in the inhibitor group). Compared with the EA group at the same time point, MVD, the expressions of mTOR, HIF-1α proteins and mRNAs and miR-126-3p in the inhibitor group were all decreased (P<0.05,P<0.01). Compared with the group itself at 4 hours after modeling and day 3 and day 7, the mNSS was decreased at day 14 （P<0.01） in the model, EA and inhibitor groups. Compared with the group itself at day 3, the MVD value and the expression of mTOR protein were increased at day 7 and day 14 in the model, EA and inhibitor groups (P<0.01, P<0.05). Compared with the group itself at day 3 and day 7, the expression of mTOR mRNA and miR-126-3p were up-regulated at day 14 in the model and EA groups (P<0.01, P<0.05).Compared with the group itself at day 3, the mRNA expressions of mTOR and HIF-1α were increased at day 7 and day 14 (P<0.01, P<0.05) in the inhibitor group. EA at GV14 and GV20 can alleviate neurological deficit and improve angiogenesis in rats with CI, which may be related with its effect in up-regulating the expression of mTOR and HIF-1α, improving activation of miR-126-3p in the cortex of ischemic penumbra.

Deferasirox and vitamin D3 co-therapy mitigates iron-induced renal injury by enhanced modulation of cellular anti-inflammatory, anti-oxidative stress, and iron regulatory pathways in rat

BackgroundChronic iron overload could induce nephropathy via oxidative stress and inflammation, and chelating therapy has limited efficacy in removing excess intracellular iron. Although vitamin D (VD) has shown potent antioxidant and anti-inflammatory effects, as well contribute to iron homeostasis, none of the previous studies measured its potential remedial effects against chronic iron toxicity. AimsTo measure the alleviating effects of deferasirox (DFX) and/or vitamin D (VD) single and combined therapies against nephrotoxicity induced by chronic iron overload. MethodsForty male rats were divided into negative (NC) and positive (PC) controls, DFX, VD, and DFX/VD groups. The designated groups received iron for six weeks followed by DFX and/or VD for another six weeks. Then, the expression pattern of renal genes and proteins including hepcidin, ferroportin (FPN), megalin, transferrin receptor 1 (TfR1), ferritin heavy and light chains, VD receptor (VDR), VD synthesizing (Cyp27b1) and catabolizing (Cyp24a1) enzymes were measured alongside serum markers of renal function and iron biochemical parameters. Additionally, several markers of oxidative stress (MDA/H2O2/GSH/SOD1/CAT/GPx4) and inflammation (IL-1β/IL-6/TNF-α/IL-10) together with renal cell apoptosis and expression of caspase-3 (Casp-3) were measured. ResultsThe PC rats showed pathological iron and renal biochemical markers, hypovitaminosis D, increased renal tissue iron contents with increased Cyp24a1/Megalin/ferritin-chains/hepcidin, and decreased Cyp27b1/VDR/TfR1/FPN expression than the NC group. The PC renal tissues also showed abnormal histology, increased inflammatory (IL-1β/IL-6/TNF-α), oxidative stress (MDA/H2O2), and apoptosis markers with decreased IL-10/GSH/SOD1/CAT/GPx4. Although DFX monotherapy reduced serum iron levels, it was comparable to the PC group in renal iron concentrations, VD and iron-homeostatic molecules, alongside markers of oxidative stress, inflammation, and apoptosis. On the other hand, VD monotherapy markedly modulated renal iron and VD-related molecules, reduced renal tissue iron concentrations, and preserved renal tissue relative to the PC and DFX groups. However, serum iron levels were equal in the VD and PC groups. In contrast, the best significant improvements in serum and renal iron levels, expression of renal iron-homeostatic molecules, oxidative stress, inflammation, and apoptosis were seen in the co-therapy group. Conclusionsiron-induced nephrotoxicity was associated with dysregulations in renal VD-system together with renal oxidative stress, inflammation, and apoptosis. While DFX reduced systemic iron, VD monotherapy showed better attenuation of renal iron concentrations and tissue damage. Nonetheless, the co-therapy approach exhibited the maximal remedial effects, possibly by enhanced modulation of renal iron-homeostatic molecules alongside reducing systemic iron levels. Availability of data and materialsAll data generated or analysed during this study are included in this published article [and its Supplementary information files].

Pien-Tze-Huang alleviates CCl4-induced liver fibrosis through the inhibition of HSC autophagy and the TGF-β1/Smad2 pathway.

Ethnopharmacological relevance: Pien-Tze-Huang (PZH)—a traditional Chinese medicine (TCM) compound—has been employed to treat various liver inflammation and tumors for over 10 decades. Interestingly, most of the pharmacological effects had been validated and explored toward liver ailment along with pro-inflammatory conditions and cancer at the cellular and molecular level to date. Aim of the study: The present study aimed to investigate the therapeutic effect of PZH on autophagy and TGF-β1 signaling pathways in rats with liver fibrosis and hepatic stellate cell line (HSC). Materials and methods: Male SD rats with carbon tetrachloride (CCl4)-induced liver fibrosis were used as the animal model. Next, PZH treatment was given for 8 weeks. Afterward, the therapeutic effects of PZH were analyzed through a hepatic tissue structure by hematoxylin-eosin (H&E), Van Gieson (VG) staining, and transmission electron microscopy (TEM), activity of ALT and AST by enzyme-associated immunosorbent assay as well. Subsequently, mRNA and protein expression were examined by quantitative polymerase chain reaction (qPCR), Western blotting, and immunohistochemistry (IHC). Then, the cell vitality of PZH-treated HSC and the expression of key molecules prevailing to autophagy were studied in vitro. Meanwhile, SM16 (a novel small molecular inhibitor which inhibits TGFβ-induced Smad2 phosphorylation) was employed to confirm PZH’s effects on the proliferation and autophagy of HSC. Results: PZH pharmacologically exerted anti-hepatic fibrosis effects as demonstrated by protecting hepatocytes and improving hepatic function. The results revealed the reduced production of extracellular collagen by adjusting the balance of matrix metalloproteinase (MMP) 2, MMP9, and tissue inhibitor of matrix metalloproteinase 1 (TIMP1) in PZH-treated CCl4-induced liver fibrosis. Interestingly, PZH inhibited the activation of HSC by down-regulating TGF-β1 and phosphorylating Smad2. Furthermore, PZH down-regulated yeast Atg6 (Beclin-1) and microtubule-associated protein light chain 3 (LC3) toward suppressing HSC autophagy, and PZH exhibited similar effects to that of SM16. Conclusion: To conclude, PZH alleviated CCl4-induced liver fibrosis to reduce the production of extracellular collagen and inhibiting the activation of HSC. In addition, their pharmacological mechanisms related to autophagy and TGF-β1/Smad2 signaling pathways were revealed for the first time.

Lin28A alleviates ovariectomy-induced osteoporosis through activation of the AMP-activated protein kinase pathway in rats.

To investigate the role of Lin28A in ovariectomy-induced osteoporosis and to elucidate the underlying molecular mechanism. Bilateral ovariectomy was conducted to generate an ovariectomy (OVX) rat model. Western blotting was performed to assess the relative expression levels of Lin28A, osteocalcin (OCN), runt-related transcription factor 2 (RUNX2), adenosine monophosphate-activated protein kinase (AMPK) and phosphorylated AMPK (p-AMPK) proteins. Enzyme-linked immunosorbent assays were performed to detect the serum levels of calcium, E2, alkaline phosphatase (ALP) and interleukin (IL)-1β. Three-point bending test was used to assess biomechanical parameters of left femoral diaphysis. Hematoxylin and eosin (HE) staining was conducted to detect the trabecular structure of bone tissue. Dihydroethidium assay kit was used to measure the intracellular reactive oxygen species (ROS) level in osteoclasts. Alizarin red staining revealed the calcium deposit in bone marrow stromal cells (BMSC). The expression levels of Lin28A, OCN, RUNX2, AMPK and p-AMPK proteins were significantly decreased in OVX rats. The serum levels of calcium, E2, ALP and IL-1β were significantly declined in OVX rats. Biomechanical parameters of left femoral diaphysis were significantly decreased in OVX rats. OVX-induced trabecular abnormalities. ROS level was dramatically increased in the bone tissue of OVX rats, and calcium deposit was dramatically decreased in BMSC cells of OVX rats. These effects induced by OVX could be prevented by overexpression of Lin28A. Lin28A alleviates ovariectomy-induced osteoporosis through activation of AMPK pathway in rats.

Exogenous hydrogen sulfide inhibits the senescence of cardiomyocytes through modulating mitophagy in rats

Hydrogen sulfide (H2S), a gaseous molecule, has been shown to be involved in the regulation of body pathophysiological processes. Aging is related to structural and functional alterations within the heart. There is evidence that diminished mitophagy accelerates the aging process. Studies in recent years have revealed that plasma levels of H2S in humans and old rats decrease with age, and H2S acts as a cytoprotective mediator in the aging process. However, it is unclear whether H2S can delay the senescence of cardiomyocytes by regulating mitophagy. Our present results showed that exogenous H2S inhibited mitochondrial damage, oxidative stress and cell apoptosis, and enhanced mitophagy through upregulating the SIRT1-PINK1-parkin pathway in myocardial tissues of aged rats and cultured aged cardiomyocytes. Furthermore, the effect of exogenous H2S on the above indicators was the same as that of SRT1720 (a SIRT1 agonist) and kinetin (a PINK1 activator). Our findings suggest that exogenous H2S inhibits the senescence of cardiomyocytes by increasing mitophagy via upregulation of the SIRT1-PINK1-parkin pathway in rats.

Effects of breviscapine on cerebral ischemia-reperfusion injury and intestinal flora imbalance by regulating the TLR4/MyD88/NF-κB signaling pathway in rats

Ethnopharmacological relevanceThe plant Erigeron breviscapus (Vant.) Hand.-Mazz.,a Chinese herbal medicine with multiple pharmacological effects and clinical applications, has been traditionally used in the treatment of paralysis caused by stroke and joint pain from rheumatism by the Yi minority people of Southwest China for generations.However, its mechanism involves many factors and has not been fully clarified. Aim of the studyTaking intestinal flora as the target, the protective effect of extract(breviscapine) of E. breviscapus on cerebral ischemia and its possible mechanism were discussed from the perspective of brain inflammatory pathway and intestinal CYP3A4, which depends on intestinal flora. Materials and methodsIn this study, we first verified the binding ability between major active ingredient of Erigeron breviscapus and the core target TLR4 protein by molecular docking using Vina software.We established a rat model of cerebral ischemia-reperfusion injury in vivo.The neurological function of rats was scored by Bederson score table, the cerebral infarction volume was detected by TTC staining, and the serum NSE level was detected by ELASA. 16S rRNA sequencing was used to detect the intestinal flora of rats in each group.The expression levels of cerebral TLR4/MyD88/NF-κB and CYP3A4 mRNA and protein in different intestinal segments were detected by qRT-PCR and Western blot. ResultsCompared with the model group, the neurological injury score, infarct volume and serum NSE concentration of breviscapine low, medium and high dose groups and nimodipine groups decreased significantly. Meanwhile, breviscapine could significantly reduce the expression level of the TLR4/MyD88/NF-κB in brain tissue and CYP3A4 in different intestinal segments of rats with cerebral ischemia-reperfusion injury. In addition, breviscapine also significantly ameliorated intestinal flora dysbiosis of rats with cerebral ischemia-reperfusion injury. ConclusionsBreviscapine can protect rats from cerebral ischemia-reperfusion injury by regulating intestinal flora, inhibiting brain TLR4/MyD88/NF-κB inflammatory pathway and intestinal CYP3A4 expression.

Cannabidiol attenuates methamphetamine-induced cardiac inflammatory response through the PKA/CREB pathway in rats.

BackgroundMethamphetamine (MA) abuse is a major global public health problem. However, it is not yet known whether cannabidiol (CBD) has protective effects on MA-induced cardiotoxicity. The present study investigated whether CBD has protective effects on MA-induced cardiac damage in rats via the protein kinase A/cyclic adenosine monophosphate (cAMP)-response element-binding protein (PKA/CREB) pathway.MethodsA total of 30 rats were randomly divided into 5 groups. The rats were administered MA (10 mg/kg) by intraperitoneal (IP) injection once a day for 4 weeks, and with CBD (40 or 80 mg/kg, IP) treatment 1 h before the MA injections. Morphological changes were determined using hematoxylin and eosin and Masson’s trichrome staining. The serum levels of interleukin (IL)-6 and IL-10 were detected using enzyme-linked immunoassay kits. The protein expression levels of cardiac troponin I (cTnI), PKA, phospho-PKA (p-PKA), CREB, and phospho-CREB (p-CREB) in the myocardium were detected by Western blot analysis.ResultsThere was no significant difference in body weight among the groups. Heart weight and the heart-to-body weight ratio were higher in the MA group than the control group, while CBD (80 mg/kg) pretreatment (CBD80 + MA group) reduced the heart weight and the heart-to-body weight ratio compared to the MA group. The chronic administration of MA resulted in a cardiac inflammatory response, the progressive development of fibrosis, and necrosis, while CBD treatment attenuated these lesions. The protein expression levels of PKA, p-PKA, CREB, and p-CREB increased following MA administration, but significantly decreased with CBD treatment. These results indicate that chronic MA administration leads to cardiotoxicity, but these effects can be attenuated by CBD pretreatment.ConclusionsThis study was the first to examine the protective effects of CBD on cardiotoxicity elicited by chronic MA exposure in rats. Our research suggests that CBD attenuates the cardiac inflammatory response induced by MA through the PKA/CREB pathway, and CBD may have potential clinical application in the treatment of MA-induced cardiotoxicity.

Abstract 074: Empagliflozin Improves Impaired Sensitivity Of Afferent Neurons With Renal Axons

Afferent renal nerve pathways likely play a role in salt sensitive hypertension. We recently reported that high salt diet (HS) impairs these afferent renal pathways in rats. Now we tested the hypothesis that during HS a decrease in sensitivity of renal afferent neurons is prevented by the SGLT2 inhibitor empagiflozin.Respective groups of rats were put on HS containing 8% NaCl or a normal diet. Two groups (HS, controls) received empagiflozin 20 mg/kg BW/day orally. Renal neurons were retrogradely labeled with DiI. In culture, labeled dorsal root ganglion neurons (DRG Th11-L2) with renal afferents were investigated electrophysiologically using current clamp mode to assess action potential generation during current injection. Neurons were characterized as tonic highly active (&gt; 5 action potentials, AP) and phasic less active neurons (≤ 5 AP upon stimulation. )In neurons from rats on HS, the relation of tonic highly active neurons to less active phasic neurons shifted consistently towards phasic units (63,8% tonic neurons in controls vs. 42%* on HS, *p&lt;0.05, z-test). However, continuous treatment with empagiflozin preserved the proportion of tonic neurons as in controls (67,9% on HS with concomitant administration of empagiflozin). In controls, empagiflozin did not affect the proportion of tonic to phasic neurons (63,8% tonic neurons in controls vs. 67,9% on HS &amp; empagliflozin, p=0.7, z-test). Blood pressure and heart rate were not altered by HS and/or treatment with any chosen dose of empagiflozin.In rats, chronically elevated sodium intake (8% NaCl) reduced the sensitivity and stimulability of renal afferent DRG neurons. Under these circumstances, concomitant treatment with the SGLT2 inhibitor empagiflozin preserved the function of renal afferent DRG neurons. SGLT 2 inhibitors may help to treat dysfunction of renal innervation in cardiovascular disease.

Preventive Electroacupuncture Alleviates Oxidative Stress and Inflammation via Keap1/Nrf2/HO-1 Pathway in Rats with Cyclophosphamide-Induced Premature Ovarian Insufficiency.

Electroacupuncture (EA) is a popular therapeutic therapy for premature ovarian insufficiency (POI). However, little has been known about the underlying processes of EA therapy. To investigate the benefit of EA and reveal the mechanism, thirty SD female rats were allocated into the control, model, sham, EA, and GnRHa groups at random. Vaginal smears were used to monitor the rats' estrous cycle. Serum liver and renal function (ALT, AST, BUN, and Cr), sex hormone (FSH, E2, and AMH), oxidative stress markers (SOD, GSH, and MDA), and inflammatory cytokine (IL6, IL1β, and TNFα) levels were measured by enzyme-linked immunosorbent assay (ELISA). Their ovary morphology was observed by hematoxylin-eosin staining. Transmission electron microscope was used to remark the ultrastructure of the granulocytes. Protein and gene expressions of Keap1/Nrf2/HO-1 pathway were detected by western blot and RT-PCR. Compared with the model group, in the EA group, the levels of serum sex hormones recovered to normal levels. Moreover, it reduced oxidative stress in rats, as demonstrated by increased SOD and GSH levels and decreased MDA levels. Meanwhile, Keap1 mRNA and protein expression dropped considerably in the EA group, while the mRNA and protein expressions of Nrf2 and HO-1 increased. We found that preventive EA might rescue rats with CTX-induced ovarian dysfunction. The anti-inflammatory and antioxidative stress properties of EA, which elevated the Keap1/Nrf2/HO-1 signaling pathway, might be the underlying mechanism. Furthermore, as compared to GnRHa, electroacupuncture did not raise the burden of the liver (ALT and AST) or the kidney (BUN and Cr). Electroacupuncture has a meaningful impact and a sufficient level of safety, making it useful for therapeutic setting in POI.

Acupuncture Improves Endometrial Angiogenesis by Activating PI3K/AKT Pathway in a Rat Model with PCOS.

Background Acupuncture, a treatment derived from traditional Chinese medicine, can effectively relieve the symptoms and improve pregnancy outcome in patients with polycystic ovary syndrome (PCOS); however, its mechanism remains unclear. This study aimed at investigating whether acupuncture could improve endometrial angiogenesis and thus endometrial receptivity via activating PI3K/AKT pathway in PCOS rats. Methods We established a rat model with PCOS, which was induced by DHEA. Acupuncture was performed every other day for 15 days, and the PI3K inhibitor (LY294002) was intraperitoneal injected 30 mins before acupuncture treatment. Females rats were mated with male SPF SD rats in a ratio of 2 : 1 after treatment and sacrificed on the 5th day when the vaginal plug was identified. The number of implantation sites was observed, followed by ovarian and endometrial morphology detected with hematoxylin-eosin staining and a scanning electron microscope, estrous cycle detected with vaginal smear analysis, and sex hormones and angiogenesis-related PI3K/AKT gene/protein expression detected with enzyme-linked immunosorbent assay, western blotting, immune histochemistry, and quantitative real-time PCR. Results Acupuncture notably improved implantation sites' number, endometrial receptivity factors including endometrial morphology, pinopodes, HOX-10, and LIF protein expression, as well as angiogenesis and PI3K/AKT pathway factors such as VEGF, VEGFR2, Ang-1, PI3K, AKT, and P-AKT gene/protein expression and the level of eNOS and NO in the endometrium of rats with PCOS; PCOS-like symptoms were alleviated as well. The efficacy of acupuncture on a rat model with PCOS was counteracted by the combination with the PI3K inhibitor. Conclusion Acupuncture improves endometrial angiogenesis by activating the PI3K/AKT pathway, thus promoting endometrial receptivity and the number of implantation sites in rats with PCOS.

Exosomes derived from human umbilical cord mesenchymal stem cells protect against papain-induced emphysema by preventing apoptosis through activating VEGF-VEGFR2-mediated AKT and MEK/ERK pathways in rats.

IntroductionChronic obstructive pulmonary disease (COPD) is a leading cause of high mortality and heavy burden in the world. Unfortunately, emphysema, as an important component of COPD, has no curative treatments currently. Recently, human umbilical cord mesenchymal stem cells-derived exosomes (hUCMSC-Ex) constitute a promising alternative approach for tissue regeneration and repair. However, the roles of hUCMSC-Ex in emphysema and its mechanism are largely unknown. Here, we investigated the effect and the action mechanism of hUCMSC-Ex in repairing emphysema induced by papain in rats.MethodsSD rats were used to establish a papain-induced emphysema model and estimate the effect and mechanism of hUCMSC-Ex treatment. H&E staining and mean linear intercept (MLI) were used to evaluate the hUCMSC-Ex effect on emphysema. Western blotting, TUNEL and miRNA-seq were used to investigate the molecular mechanisms of hUCMSC-Ex treatment in models of papain-induced emphysema.ResultsPapain treatment led to typical emphysema, while hUCMSC-Ex reversed emphysematous changes effectively. Apoptosis of endothelial cells and other types of cells were observed in models, while hUCMSC-Ex effectively prevented their apoptosis. hUCMSC-Ex repressed active caspase-3, activated VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway in emphysematous lungs. Notably, several miRNAs, such as hsa-miR-10a-5p and hsa-miR-146a-5p, were target related to the roles of hUCMSC-Ex in papain-induced emphysema through VEGF-VEGFR2-mediated AKT and MEK/ERK pathways.ConclusionshUCMSC-Ex effectively rescued the papain-induced emphysema injury through VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway.

Ameliorating effect of fluoxetine on tamoxifen-induced memory loss: The role of corticolimbic NMDA receptors and CREB/BDNF/cFos signaling pathways in rats

Tamoxifen-induced cognitive dysfunction may lead to fluoxetine consumption in patients with breast cancer. Since the brain mechanisms are unclear in tamoxifen/fluoxetine therapy, the blockade effect of hippocampal/amygdala/prefrontal cortical NMDA receptors was examined in fluoxetine/tamoxifen-induced memory retrieval. We also assessed the corticolimbic signaling pathways in memory retrieval under the drug treatment in adult male Wistar rats. Using the Western blot technique, the expression levels of the cAMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF), and cFos were evaluated in the corticolimbic regions. The results showed that pre-test administration of fluoxetine (3 and 5 mg/kg, i.p.) improved tamoxifen-induced memory impairment in the passive avoidance learning task. Pre-test bilateral microinjection of D-AP5, a selective NMDA receptor antagonist, into the dorsal hippocampal CA1 regions and the central amygdala (CeA), but not the medial prefrontal cortex (mPFC), inhibited the improving effect of fluoxetine on tamoxifen response. It is important to note that the microinjection of D-AP5 into the different sites by itself did not affect memory retrieval. Memory retrieval increased the signaling pathway of pCREB/CREB/BDNF/cFos in the corticolimbic regions. Tamoxifen-induced memory impairment decreased the hippocampal/PFC BDNF level and the amygdala level of pCREB/CREB/cFos. The improving effect of fluoxetine on tamoxifen significantly increased the hippocampal/PFC expression levels of BDNF, the PFC/amygdala expression levels of cFos, and the ratio of pCREB/CREB in all targeted areas. Thus, NMDA receptors’ activity in the different corticolimbic regions mediates fluoxetine/tamoxifen memory retrieval. The corticolimbic synaptic plasticity changes likely accompany the improving effect of fluoxetine on tamoxifen response.

Red Palm Oil Ameliorates Oxidative Challenge and Inflammatory Responses Associated with Lipopolysaccharide-Induced Hepatic Injury by Modulating NF-κβ and Nrf2/GCL/HO-1 Signaling Pathways in Rats.

Lipopolysaccharide (LPS), a well-conserved cell wall component of Gram positive bacteria, exerts its toxic effects via inducing oxidative and pro-inflammatory responses. Red palm oil (RPO) is a unique natural product with a balanced ratio of saturated and unsaturated fatty acids, with reported antioxidant and anti-inflammatory effects. In this study, we assess the protective effect and mechanistic action of RPO using a lipopolysaccharide (LPS)-induced hepatic injury model. Male Wistar rats were assigned into four groups (10 animals/group): normal control (NC), RPO, LPS and RPO + LPS. Animals in the RPO and RPO + LPS groups were administered RPO (200 μL/day) for 28 days. On the 27th day of experiment, animals in LPS and RPO + LPS groups were injected with LPS (0.5 mg/kg body weight). Animals were sacrificed 24 h later, and blood and liver tissues harvested for biochemical and molecular analysis. RPO resolved hepatic histological dysfunction induced by LPS, and lowered alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and γ-glutamyl transferase activities in the serum. Hepatic malondialdehyde and conjugated dienes, as well as pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6 and TNFα were significantly diminished (p < 0.05) by RPO pre-treatment. Activity of hepatic antioxidant enzymes including superoxide dismutase, glutathione reductase, glutathione peroxidase, as well as glutathione redox status (GSH:GSSG), and markers of antioxidant capacity that decreased as a result of LPS injection were improved by RPO pre-treatment. Mechanistically, RPO up-regulated mRNA expression of redox sensitive transcription factor Nrf2 and its downstream targets GCL and HO-1, while also suppressing the expression of NFκβ and associated inflammatory protein, Iκβ kinase (IκKβ). In conclusion, this study highlights the ameliorating effects of RPO against LPS-induced hepatic injury and revealed the Nrf2/GCL/HO-1 and NFκβ signaling axis as potential contributing mechanisms.

Xenon post-conditioning protects against spinal cord ischemia-reperfusion injury in rats by downregulating mTOR pathway and inhibiting endoplasmic reticulum stress-induced neuronal apoptosis

The purpose of this study was to determine whether xenon post-conditioning affects mTOR signaling as well as endoplasmic reticulum stress (ERS)-apoptosis pathway in rats with spinal cord ischemia/reperfusion injury. Fifty male rats were randomized equally into sham-operated group (Sham group), I/R model group (I/R group), I/R model+ xenon post-conditioning group (Xe group), I/R model+rapamycin (a mTOR signaling pathway inhibitor) treatment group (I/R+ Rapa group), and I/R model + xenon post- conditioning with rapamycin treatment group (Xe + Rapa group).. In the latter 4 groups, SCIRI was induced by clamping the abdominal aorta for 85 min followed by reperfusion for 4 h. Rapamycin (or vehicle) was administered by daily intraperitoneal injection (4 mg/kg) for 3 days before SCIRI, and xenon post-conditioning by inhalation of 1∶1 mixture of xenon and oxygen for 1 h at 1 h after initiation of reperfusion; the rats without xenon post-conditioning were given inhalation of nitrogen and oxygen (1∶ 1). After the reperfusion, motor function and histopathologic changes in the rats were examined. Western blotting and real-time PCR were used to detect the protein and mRNA expressions of GRP78, ATF6, IRE1α, PERK, mTOR, p-mTOR, Bax, Bcl-2 and caspase-3 in the spinal cord. The rats showed significantly lowered hind limb motor function following SCIRI (P < 0.01) with a decreased count of normal neurons, increased mRNA and protein expressions of GRP78, ATF6, IRE1α, PERK, and caspase-3, and elevated p-mTOR/mTOR ratio and Bax/Bcl-2 ratio (P < 0.01). Xenon post-conditioning significantly decreased the mRNA and protein levels of GRP78, ATF6, IRE1α, PERK and caspase-3 (P < 0.05 or 0.01) and reduced p-mTOR/mTOR and Bax/Bcl-2 ratios (P < 0.01) in rats with SCIRI; the mRNA contents and protein levels of GRP78 and ATF6 were significantly decreased in I/R+Rapa group (P < 0.01). Compared with those in Xe group, the rats in I/R+Rapa group and Xe+Rapa had significantly lowered BBB and Tarlov scores of the hind legs (P < 0.01), and caspase-3 protein level and Bax/Bcl-2 ratio were significantly lowered in Xe+Rapa group (P < 0.05 or 0.01). By inhibiting ERS and neuronal apoptosis, xenon post- conditioning may have protective effects against SCIRI in rats. The mTOR signaling pathway is partially involved in this process.

Knockdown of MKL1 ameliorates oxidative stress-induced chondrocyte apoptosis and cartilage matrix degeneration by activating TWIST1-mediated PI3K/AKT signaling pathway in rats

Studies have reported that megakaryocytic leukemia 1 (MKL1) is closely related to the pathological process of a variety of inflammatory diseases, but its role in osteoarthritis (OA) needs to be clarified. This study aimed to investigate the regulatory role of MKL1 in oxidative stress-induced chondrocyte apoptosis and cartilage matrix degeneration. The expressions of target mRNAs and proteins were measured by using reverse transcription-quantitative polymerase chain reaction and western blotting. ELISA assay was used to measure the levels of IL-6, IL-8, and TNF-α in chondrocytes. And commercial kits based on different spectrophotometry or colorimetry methods were performed to validate oxidative stress. CCK-8 and apoptosis kits were used to determine cell viability and apoptosis. Rat OA model was established by anterior cruciate ligament transection (ACLT), and the expression of MKL1 was interfered by injecting sh-MKL1 lentiviral vector into caudal vein. The results showed that the expression of MKL1was induced by H2O2 in chondrocytes. Knockdown of MKL1 alleviated H2O2-induced inflammation and cell apoptosis, reduced H2O2-induced oxidative stress, and improved cartilage matrix degeneration of chondrocytes. Besides, inhibition of MKL1 regulated the activation of TWIST1-mediated PI3K/AKT signaling. Further studies have found that TWIST1-mediated PI3K/AKT signaling was involved in the regulation mechanism of MKL1 on chondrocyte apoptosis and cartilage matrix degeneration. Next, intervention with MKL1 inhibited the progression of OA in rats. These results demonstrated that MKL1 regulate the apoptosis and cartilage matrix degeneration of chondrocytes via TWIST1-mediated PI3K/AKT signaling.