Streptozotocin Rats Research Articles

Effects of exogenous ghrelin treatment on oxidative stress, inflammation and histological parameters in a fat-fed streptozotocin rat model

In this study, the anti-inflammatory, antioxidative, and protective effects of ghrelin were investigated in a fat-fed streptozotocin (STZ) rat model and compared with metformin, diabetes and the healthy control groups. Histopathological evaluations were performed on H&E-stained pancreas and brain sections. Biochemical parameters were investigated by enzyme-linked immunosorbent assay. Blood glucose levels were significantly decreased with ghrelin or metformin treatments than the diabetes group. STZ administration increased brain, renal and pancreatic IL-1β, TNF-α and MDA while decreasing GPX, CAT, SOD, and NGF levels. Ghrelin increased renal GPX, CAT, NGF pancreatic GPX, SOD, CAT, NGF and brain SOD, NGF while it decreased renal, pancreatic and brain IL-1β, TNF-α and MDA levels. Ghrelin reduced neuronal loss and degeneration in the cerebral cortex and hippocampus and greatly ameliorated diabetes-related damage in pancreas. In conclusion, the data suggested that ghrelin is an effective candidate as a protectant for reducing the adverse effects of diabetes.

Deciphering the ameliorative effect of Aloe vera (L.) burm. F. extract on histopathological alterations in Streptozotocin-induced WNIN/GR-ob rats

Ethnopharmacological relevanceNatural products have emerged as a novel source in the management of non-communicable diseases, more so in diabetes mellitus and its comorbidities. Aloe vera is widely recognized for its anti-hyperglycemic and anti-hyperlipidemic properties and numerous researchers have identified component (s) from Aloe vera attributing to these therapeutic effects. Aim of the studyThe current work was undertaken to gain insight into the protective effect of Aloe vera (L.) Burm. f. extract to study the cytoarchitecture/histopathological alterations in the target organs in mutant Obese WNIN/GR-Ob rats that were made frank diabetic with streptozotocin. Materials and methodsRats were divided into five groups. 1)WNIN-GR-Ob/control group 2)WNIN-GR-Ob treated with STZ 3)WNIN-GR-Ob + STZ + Sitagliptin 4)WNIN-GR-Ob + STZ + Aloe vera 5)WNIN-GR-Ob/control group + Aloe vera. Histopathological analysis of the pancreas, kidney, liver, and adipocytes was done after 4 weeks of treatment. ResultsThe histopathological examination of STZ-induced diabetic rats revealed significant changes in all the vital organs including cell infiltration, degeneration, and necrosis. Treatment with A. vera negated most of the histopathological changes seen in STZ induced rats. Sitagliptin—which served as a positive control in the present study—reversed the alterations seen in streptozotocin rats. ConclusionConsidering the hypoglycaemic and hypolipidemic activities of Aloe vera that have been previously demonstrated by us, the present study further re-instates the therapeutic efficacy of Aloe vera towards vital organs. It was able to restore islet cells and reduce β-cell damage. In addition, it was also able to aid in kidney tubular regeneration and reverse the degenerative changes brought on by streptozotocin on liver. Further, Aloe vera treated group exhibited moderate hyperplasia with decreased size of adipocytes and reduced macrophage infiltration. Thus, our findings advocate its application as an important nutraceutical in the therapeutic management of diabetes mellitus and associated complications.

10 kHz spinal cord stimulation improves metrics of spinal sensory processing in a male STZ rat model of diabetes

To explore why clinical 10 kHz spinal cord stimulation (10 kHz SCS) might improve neurological function in a model of painful diabetic neuropathy (PDN), the short-term behavioral, electrophysiological, and histological effects of 10 kHz SCS were studied using adult male streptozotocin (STZ)-induced diabetic Sprague-Dawley rats. Four testing groups were established: Naïve controls (N = 8), STZ controls (N = 7), STZ+Sham SCS (N = 9), and STZ+10 kHz SCS (N = 11). After intraperitoneal injection (60 mg/kg) of STZ caused the rats to become hyperglycemic, SCS electrodes were implanted in the dorsal epidural space over the L5-L6 spinal segments in the STZ+Sham SCS and STZ+10 kHz SCS groups and were stimulated for 14 days. The von Frey filament paw withdrawal threshold was measured weekly. At termination, animals were anesthetized and the electrophysiologic response of dorsal horn neurons (receptive field size, vibration, radiant warmth) of the ipsilateral foot was measured. Tissue from the plantar paw surface was obtained post-euthanization for intraepidermal nerve fiber density measurements. In comparison to other control groups, while no significant effect of 10 kHz SCS on peripheral intraepidermal nerve fiber density was observed, 10 kHz SCS ‘normalized’ the central neural response to vibration, receptive field, and paw withdrawal threshold, and elevated the neural response to tissue recovery from warm stimuli. These results suggest that short-term, low intensity 10 kHz SCS operates in the spinal cord to ameliorate compromised sensory processing, and may compensate for reduced peripheral sensory functionality from chronic hyperglycemia, thereby treating a broader spectrum of the sensory symptoms in diabetic neuropathy.

Investigating the Impact of Intracerebroventricular Streptozotocin on Female Rats with and without Ovaries: Implications for Alzheimer's Disease.

To contribute to research on female models of Alzheimer's disease (AD), our aim was to study the effect of intracerebroventricular (ICV) injection of streptozotocin (STZ) in female rats, and to evaluate a potential neuroprotective action of ovarian steroids against STZ. Female rats were either ovariectomized (OVX) or kept with ovaries (Sham) two weeks before ICV injections. Animals were injected with either vehicle (artificial cerebrospinal fluid, aCSF) or STZ (3mg/kg) and separated into four experimental groups: Sham + aCSF, Sham + STZ, OVX + aCSF and OVX + STZ. Nineteen days post-injection, we assessed different behavioral aspects: burying, anxiety and exploration, object recognition memory, spatial memory, and depressive-like behavior. Immunohistochemistry and Immunoblot analyses were performed in the hippocampus to examine changes in AD-related proteins and neuronal and microglial populations. STZ affected burying and exploratory behavior depending on ovarian status, and impaired recognition but not spatial memory. STZ and ovariectomy increased depressive-like behavior. Interestingly, STZ did not alter the expression of β-amyloid peptide or Tau phosphorylated forms. STZ affected the neuronal population from the Dentate Gyrus, where immature neurons were more vulnerable to STZ in OVX rats. Regarding microglia, STZ increased reactive cells, and the OVX + STZ group showed an increase in the total cell number. In sum, STZ partially affected female rats, compared to what was previously reported for males. Although AD is more frequent in women, reports about the effect of ICV-STZ in female rats are scarce. Our work highlights the need to deepen into the effects of STZ in the female brain and study possible sex differences.

The possible effect of crude phenolic-rich extract from mushroom (Pleurotus ostreatus) on infertility induced by streptozotocin in rats fed a high-fat diet as a model of type 2 diabetes

BackgroundPhenolic compounds (PC) are found in various foods that are part of the human diet, such as mushrooms. The identification of PC is crucial due to their bioactive properties and their role in disease prevention. This study aimed to assess the antioxidant and antidiabetic properties of the phenolic component extract (PCE) derived from the Pleurotus ostreatus mushroom. The extract was separated using high-performance liquid chromatography (HLPC). The PCE was then tested on diabetic rats fed a high-fat diet (HFD). Also, this study was an attempt to treat infertility caused by type 2 diabetes in male rats.MethodsStreptozotocin (STZ) was administered to Wistar rats after a 4-week HFD as a model of type 2 diabetes (D2). Animals were given phenols orally on a high-fat diet for four weeks after being diagnosed with diabetes.ResultsPCE constituents were 48.02% carbohydrates, 21.15% protein, 6.16% fiber, 2.06% fat, and 6.93% ash. The evaluation of the PCE was carried out by assessing its retention rates and subsequently comparing the UV data to standards.Total phenols and flavonoids in the crude extract were 23.04 mg/g gallic acid equivalent and 8.14 mg/g quercetin equivalent, respectively. Catechin was found as the significant PC (121.53 µg/mL), while gallic acid was the second PC (11.64 µg/ml) in the PCE of mushrooms. PCE showed high radical scavenging activity on DPPH. With dosage and incubation duration in dark-dependent conditions, it was discovered to be 93.23% at a 500 µg/ml concentration after 120 min in the dark. PCE reduces blood glucose levels while elevating insulin levels and antioxidant activity indicators. Our results show that phenols and their bioactive components can change glucose metabolism in STZ-induced diabetic HFD rats (D2).ConclusionsThis study supports PCE's therapeutic potential in treating hyperglycemia, increasing insulin secretion, and addressing diabetes-induced infertility.

Anti-depressant effect of Naringenin-loaded hybridized nanoparticles in diabetic rats via PPARγ/NLRP3 pathway

Naringenin (NAR) has various biological activities but low bioavailability. The current study examines the effect of Naringenin-loaded hybridized nanoparticles (NAR-HNPs) and NAR on depression induced by streptozotocin (STZ) in rats. NAR-HNPs formula with the highest in vitro NAR released profile, lowest polydispersity index value (0.21 ± 0.02), highest entrapment efficiency (98.7 ± 2.01%), as well as an acceptable particle size and zeta potential of 415.2 ± 9.54 nm and 52.8 ± 1.04 mV, respectively, was considered the optimum formulation. It was characterized by differential scanning calorimetry, examined using a transmission electron microscope, and a stability study was conducted at different temperatures to monitor its stability efficiency showing that NAR-HNP formulation maintains stability at 4 °C. The selected formulation was subjected to an acute toxicological test, a pharmacokinetic analysis, and a Diabetes mellitus (DM) experimental model. STZ (50 mg/kg) given as a single i.p. rendered rats diabetic. Diabetic rat groups were allocated into 4 groups: one group received no treatment, while the remaining three received oral doses of unloaded HNPs, NAR (50 mg/kg), NAR-HNPs (50 mg/kg) and NAR (50 mg/kg) + peroxisome proliferator-activated receptor-γ (PPAR-γ) antagonist, GW9662 (1mg/kg, i.p.) for three weeks. Additional four non-diabetic rat groups received: distilled water (normal), free NAR, and NAR-HNPs, respectively for three weeks. NAR and NAR-HNPs reduced immobility time in forced swimming test and serum blood glucose while increasing serum insulin level. They also reduced cortical and hippocampal 5-hydroxyindoeacetic acid, 3,4-Dihydroxy-phenylacetic acid, malondialdehyde, NLR family pyrin domain containing-3 (NLRP3) and interleukin-1beta content while raised serotonin, nor-epinephrine, dopamine and glutathione level. PPAR-γ gene expression was elevated too. So, NAR and NAR-HNPs reduced DM-induced depression by influencing brain neurotransmitters and exhibiting anti-oxidant and anti-inflammatory effects through the activation PPAR-γ/ NLRP3 pathway. NAR-HNPs showed the best pharmacokinetic and therapeutic results.

Kv7 Channel Activators Flupirtine and ML213 Alleviate Neuropathic Pain Behavior in the Streptozotocin Rat Model of Diabetic Neuropathy.

Chronic peripheral neuropathic pain (PNP) is a debilitating condition that is associated with many types of injury/diseases, including diabetes mellitus. Patients with longstanding diabetes develop diabetic PNP (DPNP), which is resilient to currently available drugs. The underlying molecular mechanisms of DPNP are still illusive, but Kv7 channels that have been implicated in the pathogenesis of various types of chronic pain are likely to be involved. Indeed, using the streptozotocin (STZ) rat model of DPNP, we have previously shown that Kv7 activation with their non-selective activator retigabine attenuated neuropathic pain behavior suggesting that these channels are implicated in DPNP pathogenesis. Here, we evaluated, in the same STZ model, whether the more potent and more selective Kv7 channel openers flupirtine and ML213 attenuate STZ-induced pain hypersensitivity. Male Sprague Dawley rats (250-300 g) were used. The STZ model involved a single injection of STZ (60 mg/kg, i.p.). Behavioral testing for mechanical and heat pain sensitivity was performed using a dynamic plantar aesthesiometer and Hargreaves analgesiometer, respectively. STZ rats exhibited behavioral signs of mechanical and heat hypersensitivity as indicated by significant decreases in the mean paw withdrawal threshold (PWT) and mean paw withdrawal latency (PWL), respectively, at 35 days post-STZ treatment. Single injections of flupirtine (10 mg/kg, i.p.) and ML213 (5 mg/kg, i.p.) to STZ rats (35-days after STZ treatment) caused significant increases in the mean PWT, but not PWL, indicating attenuation of mechanical, but not heat hypersensitivity. Both flupirtine and ML213 were as effective as the positive control gabapentin (10/kg, i.p.), and their anti-allodynic effects were prevented by the Kv7 channel-specific blocker XE991 (3 mg/kg, i.p.). The findings suggest that Kv7 channels are involved in the mechanisms of mechanical but not heat hypersensitivity associated with DPNP, and that their activation may prove to be effective in alleviating DPNP symptoms.

Antidiabetic activity of the aqueous extract of Erigeron floribundus leaves in streptozotocin-induced type 1 diabetes model in Wistar rats

BackgroudErigeron floribundus is a herbaceous plant used in traditional Cameroonian medicine to treat diabetes mellitus. The aim of this study was to evaluate the antidiabetic properties of the aqueous extract of E. floribundus leaves (AEEF) in diabetic rats. MethodsDiabetes was induced by a single intraperitoneal injection of streptozotocin (60 mg/kg) in normal rats fasted for 16 h. Subsequently, 30 diabetic male rats were divided into groups and treated orally for 21 days with distilled water (10 mL/kg), glibenclamide (3 mg/kg) and AEEF (300, 400, and 500 mg/kg). Body weight, food and water intake, blood glucose, insulin levels, lipid and oxidative profiles, as well as some markers of liver and kidney function were assessed. Histological sections of the rats' pancreas were taken. ResultsAEEF and glibenclamide significantly increased (p < 0.001) body weight and decreased food and water intake in rats. A decrease in blood glucose (p < 0.001) and an increase in insulin levels (p < 0.001) were observed in the AEEF and glibenclamide groups. AEEF caused a significant (p < 0.001) decrease in the levels of total cholesterol, LDL-c, triglycérides and coronary risk index (CRI), accompanied by a significant (p < 0.001) increase in HDL levels and HOMA-β in rats. AEEF showed an improvement (p < 0.001) in CAT and SOD activity and GSH levels accompanied by a significant decrease (p < 0.001) in malondialdehyde levels. In addition, ALAT and ASAT activity, urea and creatinine levels were significantly reduced (p < 0.001) after treatment with AEEF and glibenclamide. The extract also improved the size of Langerhans Islets in the pancreas of diabetic rats. ConclusionAEEF contains several bioactive compounds conferring antidiabetic, anti-dyslipidemic and antioxidant properties, thus justifying its therapeutic use in the treatment of diabetes mellitus.

Harmine exhibits anti-apoptotic properties and reduces diabetes-induced testicular damage caused by streptozotocin in rats.

Diabetes mellitus induces fertility problems in men, mainly because of increased free radicals. Natural resources are effective for male infertility treatment. This study investigated the effects of harmine, an alkaloid available in Peganum harmala L., on the male reproductive system of diabetic rats. We divided 32 rats into four groups, and eight were randomly placed in each group. For diabetes induction, the animals received 50 mg/kg of streptozotocin intraperitoneally. After 1 week, animals received 15 mg/kg of harmine (28 days; intraperitoneal). Histopathological examinations, serum levels of male hormones, levels of nitric oxide (NO) and malondialdehyde (MDA) in the testes, total antioxidant capacity (TAC), insulin serum levels, fasting blood glucose levels, the apoptotic index, and semen analysis were assessed. The diabetes group exhibited morphological changes in testicular tissue, significant decreases in the diameter of the seminiferous tubule, the Johnsen score, testosterone, luteinizing hormone, follicle-stimulating hormone, insulin serum levels, and TAC in testicular tissue (p<0.01). Harmine treatment ameliorated the morphological changes in the testes and improved sperm parameters relative to the diabetes group (p<0.05). The NO and MDA levels in the testes, fasting blood glucose serum levels, and apoptotic index parameters were significantly elevated in the diabetes group, while in the diabetes+harmine group, these parameters were reduced (p<0.01). Harmine protects testicular tissue and sperm against diabetes-induced damage. This effect of harmine is associated with a rebalancing of the antioxidant capacity that subsequently decreases apoptosis in the testes.

Effect of l-carnitine alone and in combination with metformin on the behavioral and biochemical alterations induced by streptozotocin in Wistar rats

Effect of l-carnitine alone and in combination with metformin on the behavioral and biochemical alterations induced by streptozotocin in Wistar rats

Study on the role and mechanism of Tan IIA in Alzheimer’s disease based on CREB-BDNF-TrkB pathway

The occurrence and development of Alzheimer’s disease (AD) is closely related to neuronal loss, inflammatory response, cholinergic imbalance, and Tau protein hyperphosphorylation. Previous studies have confirmed that Streptozotocin (STZ) can be used to establish a rat model of AD by injecting it into the rat brain via the lateral ventricle. Our previous research showed that Danshentone IIA (Tan IIA) can improve cognitive dysfunction in rats caused by CC chemokine ligand 2, and network pharmacology results show that Tan IIA is very likely to improve AD symptoms through the cyclic adenosine monophosphate response element binding protein (CREB), brain-derived neurotrophic factor (BDNF), and tyrosine kinase receptor protein (TrkB) pathway. The results of the water maze experiment showed that after Tan IIA treatment, the escape latency of AD rats was shortened and the number of platform crossings increased; in the new object recognition experiment, the discrimination index of AD rats significantly increased after treatment; Nissl staining and Tunel staining results showed that Tan IIA increased the number of surviving neurons in the hippocampus of cognitively impaired rats and reduced neuronal apoptosis; Bielschowsky silver staining results showed that Tan IIA reduced neurofibrillary tangles (NFTs) in the AD rats; Tan IIA can reduce the inflammatory response and oxidative stress reaction in the hippocampus of AD rats, and at the same time reduce the activity of acetylcholinesterase. Tan IIA can significantly increase the expression of CREB, BDNF, TrkB in the hippocampal tissue of STZ-injured rats (P < 0.05). These data suggest that Tan IIA may upregulate the expression of the CREB-BDNF-TrkB signaling pathway in the hippocampus of brain tissue, produce anti-neuroinflammatory, antioxidant stress, inhibit neuronal apoptosis effects, and improve cholinergic neurotransmitter disorder induced by STZ, reduce the neuronal damage and learning and memory impairment caused by STZ in rats, and improve the cognitive function of rats.

A Non-Toxic Binuclear Vanadium(IV) Complex as Insulin Adjuvant Improves the Glycemic Control in Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus (DM) complications are a burden to health care systems due to the associated consequences of poor glycemic control and the side effects of insulin therapy. Recently. adjuvant therapies, such as vanadium compounds, have gained attention due to their potential to improve glucose homeostasis in patients with diabetes. In order to determine the anti-diabetic and antioxidant effects of the oxidovanadium(IV) complex (Et3NH)2[{VO(OH}2)(ox)2(µ-ox)] or Vox2), rats with streptozotocin (STZ)-induced diabetes were treated with 30 and 100 mg/kg of Vox2, orally administered for 12 days. Vox2 at 100 mg/kg in association with insulin caused a 3.4 times decrease in blood glucose in STZ rats (424 mg/dL), reaching concentrations similar to those in the normoglycemic animals (126 mg/dL). Compared to insulin alone, the association with Vox2 caused an additional decrease in blood glucose of 39% and 65% at 30 and 100 mg/kg, respectively, and an increased pancreatic GSH levels 2.5 times. Vox2 alone did not cause gastrointestinal discomfort, diarrhea, and hepatic or renal toxicity and was not associated with changes in blood glucose level, lipid profile, or kidney or liver function. Our results highlight the potential of Vox2 in association with insulin in treating diabetes.

Therapeutic Effect of Punica granatum Peels Extract against Nephropathy Induced by Streptozotocin in Rats.

Therapeutic Effect of Punica granatum Peels Extract against Nephropathy Induced by Streptozotocin in Rats.

Integrated Network Pharmacology Analysis and Experimental Validation to Elucidate the Mechanism of Acteoside in Treating Diabetic Kidney Disease.

Acteoside, an active ingredient found in various medicinal herbs, is effective in the treatment of diabetic kidney disease (DKD); however, the intrinsic pharmacological mechanism of action of acteoside in the treatment of DKD remains unclear. This study utilizes a combined approach of network pharmacology and experimental validation to investigate the potential molecular mechanism systematically. First, acteoside potential targets and DKD-associated targets were aggregated from public databases. Subsequently, utilizing protein-protein interaction (PPI) networks, alongside GO and KEGG pathway enrichment analyses, we established target-pathway networks to identify core potential therapeutic targets and pathways. Further, molecular docking facilitated the confirmation of interactions between acteoside and central targets. Finally, the conjectured molecular mechanisms of acteoside against DKD were verified through experimentation on unilateral nephrectomy combined with streptozotocin (STZ) rat model. The underlying downstream mechanisms were further investigated. Network pharmacology identified 129 potential intersected targets of acteoside for DKD treatment, including targets such as AKT1, TNF, Casp3, MMP9, SRC, IGF1, EGFR, HRAS, CASP8, and MAPK8. Enrichment analyses indicated the PI3K-Akt, MAPK, Metabolic, and Relaxin signaling pathways could be involved in this therapeutic context. Molecular docking revealed high-affinity binding of acteoside to PIK3R1, AKT1, and NF-κB1. In vivo studies validated the therapeutic efficacy of acteoside, demonstrating reduced blood glucose levels, improved serum Scr and BUN levels, decreased 24-hour urinary total protein (P<0.05), alongside mitigated podocyte injury (P<0.05) and ameliorated renal pathological lesions. Furthermore, this finding indicates that acteoside inhibits the expression of pyroptosis markers NLRP3, Caspase-1, IL-1β, and IL-18 through the modulation of the PI3K/AKT/NF-κB pathway. Acteoside demonstrates renoprotective effects in DKD by regulating the PI3K/AKT/NF-κB signaling pathway and alleviating pyroptosis. This study explores the pharmacological mechanism underlying acteoside's efficacy in DKD treatment, providing a foundation for further basic and clinical research.

Vitis vinifera L. seed standardized extract; a promising therapeutic against metabolic syndrome induced by high-fat/high-carbohydrate diet and streptozotocin in rats

Metabolic syndrome (MetS) is a group of abnormal disorders; hypertension, glucose intolerance, dyslipidemia, proinflammatory, and prothrombotic states, affecting approximately 14 % of the world's population. The potential of grape seeds extract (GSE) supplementation to improve the metabolic disturbances and their related conditions like obesity, type 2 diabetes, and nonalcoholic fatty liver disease was investigated in this study. In-vitro metabolic syndrome assays were investigated through α-amylase, α-glucosidase, lipase, lipoxygenase (LOX), cyclooxygenases (COX-1 and COX-2), renin and angiotensin converting enzyme (ACE) inhibition assays. Additionally, in-vivo rat model of high-fat-high-carbohydrate diet (HFD)-induced MetS was established, where metformin (MT) (200 mg/kg) was used as a reference drug and GSE was given at 100 and 200 mg/kg by oral gavage. GSE was standardized using HPLC analysis for the major reported compound; catechin which should be ≥ 160.76 ± 5.52 μg/mL. Total phenolic content of GSE was 21.12±0.61 µg gallic acid equivalent/1 mg extract and total flavonoid content was 23.81±0.64 µg rutin equivalent/1 mg extract. In-vitro assays revealed the potential of GSE to manage the metabolic syndrome, besides its strong antioxidant capacity. Treatment with GSE (100 mg/kg and 200 mg/kg) markedly (P < 0.05) controlled the weight gain, improved the metabolic pathways (total glucose, cholesterol, triglycerides, AST, and ALT), oxidative stress parameters (MDA, GSH, and catalase) and inflammatory biomarkers in HFD fed rats. GSE downregulated the expression of insulin resistance gene (IR) and some inflammatory related genes (TNF-α and NF-κB), additionally it improved the pathological features of metabolic conditions and upgraded the expression of Nrf2 compared to HFD group. The superior effects were owned to the high dose of GSE, 200 mg/kg b.wt. (P < 0.05, P < 0.001). All results sustenance the beneficial effects of the standardized GSE in the management of metabolic syndrome.

Proteomic Analysis of a Rat Streptozotocin Model Shows Dysregulated Biological Pathways Implicated in Alzheimer's Disease.

Alzheimer's Disease (AD) is an age-related neurodegenerative disorder characterized by progressive memory loss and cognitive impairment, affecting 35 million individuals worldwide. Intracerebroventricular (ICV) injection of low to moderate doses of streptozotocin (STZ) in adult male Wistar rats can reproduce classical physiopathological hallmarks of AD. This biological model is known as ICV-STZ. Most studies are focused on the description of behavioral and morphological aspects of the ICV-STZ model. However, knowledge regarding the molecular aspects of the ICV-STZ model is still incipient. Therefore, this work is a first attempt to provide a wide proteome description of the ICV-STZ model based on mass spectrometry (MS). To achieve that, samples from the pre-frontal cortex (PFC) and hippocampus (HPC) of the ICV-STZ model and control (wild-type) were used. Differential protein abundance, pathway, and network analysis were performed based on the protein identification and quantification of the samples. Our analysis revealed dysregulated biological pathways implicated in the early stages of late-onset Alzheimer's disease (LOAD), based on differentially abundant proteins (DAPs). Some of these DAPs had their mRNA expression further investigated through qRT-PCR. Our results shed light on the AD onset and demonstrate the ICV-STZ as a valid model for LOAD proteome description.

Are insulin sensitizers the new strategy to treat Type 1 diabetes? A long-acting dual amylin and calcitonin receptor agonist improves insulin-mediated glycaemic control and controls body weight.

Insulin therapies for Type 1 diabetes (T1D) have limitations, such as glucose fluctuations, hypoglycaemia, and weight gain. Only pramlintide is approved with insulin. However, its short half-life limits efficacy, requiring multiple daily injections and increasing hypoglycaemia risk. New strategies are needed to improve glycaemic control. Dual amylin and calcitonin receptor agonists are potent insulin sensitizers developed for Type 2 diabetes (T2D) as they improve glucose control, reduce body weight, and attenuate hyperglucagonemia. However, it is uncertain if they could be used to treat T1D. Sprague Dawley rats received a single intravenous injection of streptozotocin (STZ) (50 mg·kg-1) to induce T1D. Humulin (1 U/200 g·day-1 or 2 U/200 g·day-1) was continuously infused, while half of the rats received additional KBP-336 (4.5nmol·kg-1 Q3D) treatment. Bodyweight, food intake, and blood glucose were monitored throughout the study. An oral glucose tolerance test was performed during the study. Treatment with Humulin or Humulin + KBP-336 improved the health of STZ rats. Humulin increased body weight in STZ rats, but KBP-336 attenuated these increases and maintained a significant weight loss. The combination exhibited greater blood glucose reductions than Humulin-treated rats alone, reflected by improved HbA1c levels and glucose control. The combination prevented hyperglucagonemia, reduced amylin levels, and increased pancreatic insulin content, indicating improved insulin sensitivity and beta-cell preservation. The insulin sensitizer KBP-336 lowered glucagon secretion while attenuating insulin-induced weight gain. Additionally, KBP-336 may prevent hypoglycaemia and improve insulin resistance, which could be a significant advantage for individuals with T1D seeking therapeutic benefits.

Hippocampal acetylcholine receptor activation-dependent long-term depression in streptozotocin-induced diabetic rats

Cholinergic innervation of the hippocampus correlates with memory formation. In a well-established animal model of type 1 diabetes mellitus, obtained by injecting young adult rats with streptozotocin (STZ), reductions have been reported in the expression of acetylcholine receptors and choline acetyltransferase. In this study, we showed that long-term synaptic depression (LTD) induced by carbachol (CCh), a nonselective cholinergic receptor agonist, at Schaffer collateral-CA1 synapses in hippocampal slices was significantly weaker in streptozotocin-induced diabetic rats (STZ rats) than in age-matched control rats. No significant change was observed in the paired-pulse ratio between before and 80 min after the application of CCh in control and STZ rats. Moreover, CCh-induced LTD in control and STZ rats was not affected by an NMDA receptor antagonist. Although the application of CCh down-regulated the surface expression of GluA2 in the hippocampus of control rats, but not STZ rats. Therefore, the present results suggest that acetylcholine receptor-mediated LTD in STZ rats requires the internalization of AMPA receptors on the postsynaptic surface and their intracellular effects in the hippocampus.

Development of oral formulation of Lepidium seeds significantly decreases the high blood glucose levels in diabetic rats: in vitro formulation and in vivo antidiabetic performance

Background Lepidium sativum, Garden Cress (GC), seeds have a lot of natural molecules with a pronounced activity against different disorders. It was reported that GC seeds have the ability to lower the blood glucose level. Aim The aim of this work was to formulate GC seeds into oral tablets containing a fixed dose of the grounded seeds. Furthermore, the anti-diabetic performance of the prepared tablets was studied in the streptozotocin rats’ model in comparison with positive control metformin. Methods Micrometrics of GC grounded seeds with different excipients were investigated. Then, GC tablets were prepared via direct compression technique. GC tablets were characterized for their uniformity of dosage unit, friability, hardness, disintegration time, and in vitro release. The antidiabetic effect was studied in rats for a period of 28 days. Glycosylated hemoglobin, liver performance, and lipid levels include total cholesterol (TC), triglycerides (TGs), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were also estimated. In addition, histopathological study of liver and pancreas was also performed. Results Prosolv®EasyTab produced tablets with higher hardness, lower disintegration time, and fast release. GC tablets significantly lower the elevated blood glucose level. In addition, they have antihyperlipidemic activity, hepatocellular protective role and restore the histology of the liver and pancreas. Conclusion GC tablets could be a promising alternative formulation to control the high blood glucose level in diabetic rats rather than chemically derivatized drugs.

Improvement of Learning and Memory by Chickpeas (Cicer arietinum L.) Sprout Against Streptozotocin and Induced Amnesia in Rats

Improvement of Learning and Memory by Chickpeas (Cicer arietinum L.) Sprout Against Streptozotocin and Induced Amnesia in Rats