mRNA Levels Of p38MAPK Research Articles

Excessive dietary soluble arabinoxylan impairs the intestinal physical and immunological barriers via activating MAPK/NF-κB signaling pathway in rainbow trout (Oncorhynchus mykiss)

Arabinoxylan (AX) has been deemed as an antinutritional factor, but limited information has addressed the effects of dietary AX on intestinal health of fish. The present study investigated the effects of dietary AX on intestinal mucosal physical and immunological barriers of rainbow trout (Oncorhynchus mykiss). Five isoproteic and isolipidic experimental diets (AXE, AX0, AX2.5, AX5 and AX10) were formulated to contain 0.03% arabinoxylanase as well as 0%, 2.5%, 5% and 10% AX, respectively. Each diet was randomly distributed to triplicate groups of 35 juvenile (average weight 3.14 ± 0.02 g) per tank in a rearing system maintained at 17 ± 1 °C for 9 weeks. Dietary AX supplementation regardless of inclusion levels significantly (P < 0.05) depressed the growth performance and feed utilization. The plasma endothelin-1 and d-lactic acid contents as well as diamino oxidase activity were significantly higher in fish fed diet AX10 compared to fish fed diet AX0. Dietary inclusion of 5–10% AX resulted in decreased intestinal villus height, goblet cell number and desmosome density, increased crypt depth, short and irregular microvilli, widened intercellular space; down-regulated the mRNA levels of occludin in hindgut, claudin3 and ZO-1 in foregut and midgut, but up-regulated the mRNA levels of claudin12 and claudin15 in midgut as well as claudin23 in foregut, midgut and hindgut. Furthermore, dietary 5–10% AX supplementation decreased the midgut and hindgut complement 3, complement 4 and sIgT contents as well as the midgut IgM and hindgut IL-10 contents. Conversely, the hindgut TNF-α and IL-6 contents increased with the rising dietary AX level. RT-qPCR demonstrated that the pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-12β, IFN-γ, and TNF-α) and pIgR mRNA levels in midgut and hindgut were up-regulated by dietary AX inclusion of 5–10% AX. Meanwhile, the mRNA levels of p38 MAPK, IκBα, and NF-κB p65 in midgut and hindgut raised gradually with the increasing dietary AX content. The Western blot results showed that the protein expression levels of p38 MAPK and NF-κB generally increased with the rising dietary AX content. Dietary treatment with 0.03% arabinoxylanase did not affect the growth performance and intestinal health of rainbow trout (P > 0.05). In conclusion, excessive dietary AX inclusion (5–10%) increased the intestinal permeability and induced the intestinal inflammatory response via activating MAPK/NF-κB signaling pathway, and ultimately damaged the intestinal barrier function of rainbow trout.

Effect of a Plateau Environment on the Oxidation State of the Heart and Liver through AMPK/p38 MAPK/Nrf2-ARE Signaling Pathways in Tibetan and DLY Pigs.

Simple SummaryPlateau stress is a main factor limiting pig production. There are great differences in oxidation state and antioxidant defense between Tibetan pigs (TPs) and DLY pigs exposed to a plateau environment. However, there are limited reports on the mechanism of adaptation of TPs and DLY pigs to the plateau environment involving a signal pathway related to oxidation state. In the present study, we found that TPs exhibit a stronger heart and liver antioxidant stress capacity than DLY pigs through AMPK/p38 MAPK/Nrf2-ARE signaling pathways under a plateau hypoxic environment.This study evaluated the effect of a plateau environment on the heart and liver oxidation state of Tibetan pigs (TPs) and DLY pigs through analyzing AMPK, p38 MAPK, and Nrf2 signaling pathways. Twelve 120-day-old TPs and twelve 120-day-old DLY pigs were randomly divided into two groups in a plateau environment for three weeks. Exposed to a plateau environment, TPs exhibited a lower (p < 0.05) malondialdehyde level but higher (p < 0.05) glutathione, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC) activities in the liver and heart than those observed in DLY pigs. TPs also showed higher (p < 0.05) mRNA levels of SOD and GSH-Px in the liver and heart compared with those of DLY pigs. The TPs showed higher (p < 0.05) mRNA and protein levels of AMPK and Nrf2 in the liver and heart compared with those of DLY pigs. Furthermore, TPs showed higher (p < 0.05) mRNA and protein levels of p38 MAPK in the heart and higher mRNA levels of p38 MAPK in the liver compared with those of DLY pigs under a plateau environment. In summary, TPs possess a stronger antioxidant capacity in the heart and liver than that of DLY pigs in a plateau environment through AMPK/p38 MAPK/Nrf2-ARE signaling pathways.

Ginaton injection alleviates cisplatin-induced renal interstitial fibrosis in rats via inhibition of apoptosis through regulation of the p38MAPK/TGF-β1 and p38MAPK/HIF-1α pathways.

Ginaton injection (Ginkgo biloba extract; GBE) has been reported to protect against cisplatin-induced acute renal failure in rats. In the present study, the effects and molecular mechanisms of GBE on cisplatin-induced renal interstitial fibrosis were evaluated using a rat model. The rats were intraperitoneally injected with cisplatin once on the first day and a subset of rats were treated with GBE or SB203580 (SB; a specific p38 MAPK inhibitor) daily from days 22 to 40. The levels of N-acetyl-β-D-Glucosaminidase (NAG) in the urine, and of urea nitrogen (BUN) and creatinine (Scr) in the blood were assessed. The damage and fibrosis of renal tissues were evaluated using hematoxylin and eosin staining, as well as Masson's trichrome staining, respectively. Apoptosis in renal tissues was detected using a TUNEL assay. The protein expression levels of α-smooth muscle actin (SMA), collagen 1 (Col I), Bax, Bcl-2, caspase-3/cleaved caspase-3, hypoxia-inducible factor-1α (HIF-1α), TGF-β1 and p38MAPK, as well as the mRNA levels of p38MAPK in renal tissues were investigated. The results showed that GBE markedly reduced the levels of urinary NAG, Scr and BUN, and renal expression of α-SMA and Col I levels were also reduced. Furthermore, GBE significantly reduced renal tissue injury and the relative area of renal interstitial fibrosis induced by cisplatin. GBE effectively reduced the apoptotic rate of renal tissues, the protein expression levels of Bax, cleaved caspase-3, phospho-p38MAPK, TGF-β1 and HIF-1α, as well as the mRNA expression levels of p38MAPK in renal tissues induced by cisplatin, whereas GBE significantly increased Bcl-2 protein expression. SB exhibited similar effects to GBE, although it was not as effective. In summary, the present study is the first to show that GBE significantly alleviated renal interstitial fibrosis following cisplatin-induced acute renal injury. The mechanisms by which GBE exhibited its effects were associated with the inhibition of apoptosis via downregulation of the p38MAPK/TGF-β1 and p38MAPK/HIF-1α signaling pathways.

Electroacupuncture for pain relief in labour inhibits spinal p38 MAPK-mediated prostaglandin E2 release and uterine prostaglandin E2 receptor expression in rats.

p38 mitogen-activated protein kinase (p38 MAPK) activation involves the release of prostaglandin E2 (PGE2) and hyperalgesia. We have previously reported that electroacupuncture (EA) relieves labour pain, but the potential mechanisms remain unclear. To observe the effects of EA on labour pain intensity, serum PGE2 levels and the p38 MAPK signalling pathway in rats during labour. Female rats copulated with male rats to induce pregnancy, and then received castor oil to trigger labour. During labour, rats remained untreated (Control group, n=30) or were treated with remifentanil (n=30) or EA at Jiaji (n=30) or SP6+LI4 (n=30), respectively. The warm water tail-flick test was used to assess labour pain. Serum PGE2 levels were measured by ELISA. Protein expression of prostaglandin E2 receptor (PGER2), p38 MAPK and phospholipase A2 (PLA2) were analysed by Western blotting, and mRNA levels were measured by real-time PCR. EA treatment at Jiaji or SP6+LI4 significantly relieved labour pain, decreased serum PGE2 levels and inhibited protein and gene expression of PGER2 in the myometrium. Moreover, EA reduced protein expression of PLA2 and p38 MAPK, and inhibited phosphorylation of p38 MAPK in the lumbar spinal cord but not in the cerebral grey matter. Additionally, EA markedly decreased mRNA levels of p38 MAPK in the lumbar spinal cord and significantly reduced PLA2-IV mRNA levels in both the lumbar spinal cord and cerebral grey matter. This study indicates that EA relieves labour pain through, at least in part, inhibition of spinal p38 MAPK-mediated PGE2 release and uterine PGER2 expression in rats.

Atorvastatin Pretreatment Attenuates Ischemic Brain Edema by Suppressing Aquaporin 4

Background: Cerebral edema, a serious complication of acute cerebral infarction, has a crucial impact on morbidity and mortality in the early stage of cerebral infarction. And aquaporin 4 (AQP4), a bidirectional water transporting protein, plays a pivotal role in edema formation. At experimental model, it has proven that atorvastatin could exert pleiotropic neuroprotection on acute cerebral infarction independent of its cholesterol-lowering action. It was a common protective manifestation that atorvastatin can reduce the infarct volume and cerebral edema. However, little is known about atorvastatin improving ischemic brain edema by regulating AQP4 expression. This study intended to investigate the neuroprotection effects of atorvastatin pretreatment in rats with cerebral ischemia and further explore the potential relationship between atorvastatin and AQP4 expression. Methods: Fifty-one adult male Sprague Dawley rats were randomly divided into 3 groups: sham, middle cerebral artery occlusion (MCAO), and atorvastatin pretreatment (Ator) group. For Ator group, 20 mg/kg of atorvastatin injectable suspension was administered once for 7days by gavage before operation, whereas the others were administered the same volume of saline matching. Except for sham group, MCAO and Ator groups were subjected to permanent MCAO by modified intraluminal suture method. Infarct volume, neurological deficit, brain water content (BWC), immunohistochemistry, western blot, and polymerase chain reaction (PCR) were measured at 24 hours after MCAO. Results: Compared with sham group, the mNSS, infarct volume, and BWC of ischemic hemisphere were significantly increased (P < 0.001) in MCAO group. Positive cells and protein levels of p-p38MAPK and AQP4 in peri-infarction were significantly increased (P < 0.01). The mRNA levels of p38MAPK and AQP4 were also prominently upregulated (P < 0.01). Interestingly, preadministration of atorvastatin dramatically decreased infarct volume and the BWC of ischemic hemisphere compared with MCAO group (P < 0.05). The overexpressions of p-p38MAPK and AQP4 in peri-infarction were significantly decreased (P < 0.05) and their mRNA levels were downregulated by atorvastatin pretreatment (P < 0.05). Neurological deficits were also dramatically improved (P < 0.001). Conclusion: To the best of our knowledge, this is the first study that demonstrates an effect of atorvastatin on expression of AQP4, and we propose that decreased AQP4 expression through a p38MAPK-suppression pathway may be the mechanism of atorvastatin alleviating ischemic cerebral edema.

Effects of inhibiting peritoneal macrophage caspase recruitment domain-containing protein 9 on inflammatory reaction of severe acute pancreatitis in rats

Objective To investigate the effects of caspase recruitment domain-containing protein 9 (CARD9) expression in peritoneal macrophages on severe acute pancreatitis (SAP) in rats and its mechanism. Methods A total of 60 male Sprague Dawley rats were divided into control group (n=6), SAP group (n=18), small interfering RNA (siRNA) control group (n=18) and siRNA CARD9 group (n=18). SAP rat models were established. At three, six and twelve hours after the models were established, ascites was collected, peritoneum was lavaged and peritoneal macrophages were isolated and cultured. The expressions of CARD9, nuclear factor-kappaB (NF-κB), p38 mitogen-activated protein kinase (p38MAPK) at mRNA level in peritoneal macrophages was measured by real-time polymerase chain reaction (RT-PCR). The levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in peripheral blood were detected by enzyme-linked immunosorbent assay (ELISA). LSD or Tamhane′s T2 methods were performed for statistical analysis. Results At three, six and twelve hours after the models were established, CARD9 mRNA levels of peritoneal macrophages in SAP group were 1.63±0.05, 1.68±0.24 and 2.61±0.02, respectively, which were all higher than that of control group (1.01±0.23), and the differences were statistically significant (t=25.97, 6.86 and 131.59; all P<0.05); the levels of CARD9 mRNA of siRNA CARD9 group were 1.45±0.02, 1.24±0.03 and 1.63±0.03, respectively, which were lower than that of SAP group at the same time points, and the differences were statistically significant (t=-7.81, -4.46 and -62.13; all P<0.05). At three, six and twelve hours after the models were established, the mRNA levels of NF-κB and p38MAPK of peritoneal macrophages of rats in SAP group were 1.51±0.08, 1.81±0.10, 2.30±0.05 and 1.37±0.13, 1.69±0.18, 2.42±0.23, respectively, which were higher than those of control group (1.00±0.01, 1.03±0.08), and the differences were statistically significant (tNF-κB=15.10, 19.95 and 60.36; tp38MAPK=5.37, 8.34 and 14.11; all P<0.05); the levels of NF-κB mRNA in siRNA CARD9 group were 1.38±0.05, 1.57±0.06 and 1.76±0.09, respectively, which were lower than that of SAP group at the same time points, and the differences were statistically significant (t=-3.32, -5.07 and -12.70; all P<0.05). At six and twelve hours after the models were established, the p38MAPK mRNA levels of siRNA CARD9 group were 1.50±0.10 and 2.00±0.09, respectively, which were lower than that of SAP group, and the differences were statistically significantly (t=-2.30 and -4.17, both P<0.05). At three, six and twelve hours after the models were established, the levels of TNF-α, IL-1β and IL-6 in peripheral blood of SAP group were (53.49±21.64) pg/mL, (108.62±22.76) pg/mL and (139.00±15.35) pg/mL; (43.86±18.30) pg/mL, (87.51±17.10) pg/mL and (117.27±14.57) pg/mL; (78.38±32.70) pg/mL, (156.39±30.56) pg/mL and (209.56±26.09) pg/mL, respectively, which were higher than those of control group ((2.79±1.17), (7.13±4.52), (12.73±8.08) pg/mL), and the differences were statistically significant (tTNF-α=5.73, 11.37 and 21.69; tIL-1β=4.77, 11.13 and 17.68; tIL-6=4.77, 11.32 and 17.68; all P<0.05). At six and twelve hours after the models were established, the levels of TNF-α, IL-1β and IL-6 of siRNA CARD9 group were (75.73±16.93) pg/mL, (108.23±14.02) pg/mL; (63.05±11.98) pg/mL, (91.56±14.28) pg/mL and (112.67±21.40) pg/mL, (163.62±25.51) pg/mL, respectively, which were lower than those of SAP group, and the differences were statistically significant (tTNF-α=-2.84, -3.63; tIL-1β=-2.88, -3.09; tIL-6=-2.88, -3.09; all P<0.05). Conclusions There are CARD9-related NF-κB and p38MAPK pathways in peritoneal macrophages of SAP rats. Intervention of the expression of CARD9 in peritoneal macrophages, especially at early stage of SAP may relieve the inflammation reaction and pancreatic injury, which may provide a new method for SAP treatment. Key words: Macrophages, abdominal cavity; NF-kappaB; p38 mitogen-activated protein kinases; RNA, small interfering; Rats; Pancreatitis, severe acute; Caspase recruitment domain-containing protein 9