Underlying biochemical effects of intermittent fasting, exercise and honey on streptozotocin-induced liver damage in rats

Impact of time-restricted feeding on glycemic indices, vascular oxidative stress, and inflammation in an obese prediabetes rat model induced by a high-fat diet and sugar drink

OBJECTIVE

This study aims to investigate the effects of time-restricted feeding (TRF) on glycaemic indices and aortic tissue oxidative stress and inflammation in an obese prediabetes rat model.

METHODS AND PROCEDURES

Male Sprague-Dawley rats were divided into two normal and four obese groups. Obese prediabetes was induced by feeding a high-fat diet and sucrose water (HFSD) for 10 weeks; normal rats were given a standard diet and plain water. For the next 6 weeks, rats were grouped into the normal group (NR), which continued on the standard diet; the normal group was switched to TRF with the standard diet (NR + TRFSD); the prediabetes group (OR) was continued on HFSD; the prediabetes group was switched to TRF of HFSD (OR + TRFHFSD); the prediabetes group was switched to TRF of the standard diet (OR + TRFSD); and the prediabetes group was switched to the standard diet (OR + SD). Rats were then sacrificed, and aortic tissues were isolated and quantified for oxidative stress markers malondialdehyde, antioxidant enzyme superoxide dismutase, and inflammation markers tumor necrosis factor-α, and interleukin 1. Fasting blood glucose (FBG), body weight, Lee's index, serum insulin level, and resistance (Homeostatic Model Assessment of Insulin Resistance) were also measured.

RESULTS

Mean FBG and body weight in obese groups were higher compared to the normal groups after 10 weeks of HFDSD. Both obese-prediabetes groups that underwent TRF had reduced levels of tumor necrosis factor-α, interleukin 1, body weight, Lee's index, FBG, and insulin resistance. Furthermore, obese prediabetes on TRF with SD also reduced levels of lipid peroxidation (malondialdehyde), insulin levels and increased levels of the antioxidant enzyme (superoxide dismutase).

CONCLUSION

TRF reduced weight, improved glycaemic indices, vascular oxidative stress, and inflammation in obese-prediabetic rats.

Time Restricted Eating: A Valuable Alternative to Calorie Restriction for Addressing Obesity?

PURPOSE OF REVIEW

In this review, we summarize the molecular effects of time-restricted eating (TRE) and its possible role in appetite regulation. We also discuss the potential clinical benefits of TRE in obesity.

RECENT FINDINGS

TRE is an emerging dietary approach consisting in limiting food intake to a specific window of time each day. The rationale behind this strategy is to restore the circadian misalignment, commonly seen in obesity. Preclinical studies have shown that restricting food intake only during the active phase of the day can positively influence several cellular functions including senescence, mitochondrial activity, inflammation, autophagy and nutrients' sensing pathways. Furthermore, TRE may play a role by modulating appetite and satiety hormones, though further research is needed to clarify its exact mechanisms. Clinical trials involving patients with obesity or type 2 diabetes suggest that TRE can be effective for weight loss, but its broader effects on improving other clinical outcomes, such as cardiovascular risk factors, remain less certain. The epidemic proportions of obesity cause urgency to find dietary, pharmacological and surgical interventions that can be effective in the medium and long term. According to its molecular effects, TRE can be an interesting alternative to caloric restriction in the treatment of obesity, but the considerable variability across clinical trials regarding population, intervention, and follow-up duration makes it difficult to reach definitive conclusions.

Therapeutic effect of coenzyme-Q10 pretreatment on isoprenaline-induced cardiogenic hepatorenal complications in rats

OBJECTIVES

The significant correlation between acute myocardial infarction and subsequent hepatorenal dysfunction could result in a higher mortality rate in patients. The study aimed to evaluate the effect and mechanisms of coenzyme-Q10 (Q10) administration on hepatorenal dysfunction in an isoprenaline (ISO)-induced myocardial infarction model in rats.

MATERIALS AND METHODS

Twenty male rats were assigned into four groups (n = 5). Groups 1-2 were administered intraperitoneally with normal saline, groups 3-4 were pretreated with Q10 (10 mg/kg, i.p.) for 28 days, and groups 2 and 4 received ISO (200 mg/kg, i.p.) on the last two days. Body, kidney, and liver weights, antioxidants and biochemical biomarkers, and histopathological investigation of the liver and kidney tissues were performed.

RESULTS

The administration of ISO significantly (P < 0.05) increased oxidative stress and altered the liver and renal function integrity and morphology. Pretreatment with Q10 demonstrated a protective effect against biochemical and histological alterations through significantly enhanced antioxidant actions, notably increasing the levels of superoxide dismutase, catalase, glutathione, and glutathione transferase; reduced liver enzymes (aspartate transaminase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase), decreased urea and creatinine concentrations and reduced the gravity of histomorphological changes in hepatic and renal tissues of ISO treated rats.

CONCLUSION

Overall, our result suggests that Q10 confers hepatic and renal protection against ISO-induced hepatorenal dysfunction accompanying myocardial infarction through its antioxidant effects and amelioration of fibrotic changes.

Epigallocatechin-gallate attenuates rapamycin exacerbated high fat diet-induced autophagy, hormonal dysregulation, testicular and brain oxidative stress, and neurochemical changes in rats

This study investigated whether epigallocatechin-gallate (EGCG) could counteract the detrimental effects of high-fat diet (HFD)-induced obesity in rats exposed to rapamycin-induced reproductive and neuronal changes. Six rats per treatment group (n = 6) were utilized, in which groups 1 and 2 had dimethylsulfoxide (DMSO) (0.1%) and EGCG (80 mg/kg) respectively. Group 3 received HFD + 0.1% DMSO daily for 56 days. Group 4 received HFD + rapamycin (1 mg/kg) orally for 56 days. Rats in group 5 received HFD for 56 days and EGCG (80 mg/kg, p.o.) from days 29-56. Group 6 received the combination of HFD + rapamycin (56 days) with EGCG (80 mg/kg) from days 29-56. Cognitive loss was assessed using Y-maze-test (YMT). Afterwards, serum sex hormones, insulin-glucose balance, serotonin concentration, acetylcholinesterase activity, sperm features, antioxidants, and the markers of oxido-nitrergic, autophagy and apoptotic mediators were assessed. EGCG reversed rapamycin exacerbated HFD-induced alterations in spermatogenesis, insulin-glucose balance, reproductive hormones, oxido-nitrergic stress, and altered serotonin, acetylcholinesterase levels, and autophagic and apoptotic activities in rats' testes and brains respectively. EGCG significantly attenuated HFD-induced cognitive loss. The study showed that EGCG attenuated rapamycin-mediated HFD-induced spermatogenesis deficiency and cognitive impairment via normalization of reproductive hormones, testicular and brain oxidative stress, apoptotic, autophagic activities, with serotonin and cholinergic levels in rats.

Nano-Stevia reduces the liver injury caused by streptozotocin (STZ)-induced diabetes in rats by targeting PEPCK/GCK genes, INSR pathway and apoptosis

Objectives

Extensive application of stevia in the treatment of type 2 diabetes mellitus (DM) has been proven by a large number of previous studies. We prepared stevia loaded in nanoniosomes (nanostevia) to improve its bioavailability, functionality, and stability and explore its protective effects and underlying mechanisms in the liver of STZ-induced diabetic rats.

Methods

Single-dose intraperitoneal injection of STZ (50 mg/kg body weight) was used to establish diabetic model. The mRNA levels of PEPCK and GCK genes and the protein level of INSR were evaluated by Real time-PCR and Western blot assays, respectively. TUNEL assay was used to detect apoptotic cell death in the liver tissue.

Results

Diabetic rats exhibited significantly reduced levels of INSR (*** P < 0.001) as well as elevated levels of PEPCK (*** P < 0.001). Both stevia and nano-stevia were capable of increasing levels of GCK and INSR and reducing levels of PEPCK (## P < 0.01 and ### P < 0.001, respectively). In addition, significantly increased number of apoptotic cell death was seen in the liver tissue of diabetic rats (*** P < 0.001) which was markedly mitigated by treatment with both Stevia and nano-Stevia (#P < 0.05 and ## P < 0.01, respectively).

Conclusion

Both stevia and nano-stevia demonstrates potent anti-apoptotic activity in the liver tissue of diabetic rats by targeting PEPCK/GCK genes and INSR pathway. These finding show that nano-stevia has more potential to reduce the liver injury caused by STZ-induced diabetes in rats and hence can be considered a valid agent and alternative therapy for attenuating complications of type 2 DM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-023-01278-2.

Antihypertensive and antihyperglycemic effects of combinations of losartan with metformin and/or glibenclamide in desoxycorticosterone acetate and streptozotocin-induced hypertensive diabetic rats

BACKGROUND

Hypertension is a medical condition that often comorbidly exist in patients with type II diabetes. Therefore, it is very important to manage both conditions simultaneously to mitigate the complications and mortality connected with this comorbidity. Hence, this study investigated the antihypertensive and antihyperglycemic effects of combinations of losartan (LOS) with metformin (MET) and/or glibenclamide (GLB) in hypertensive diabetic rats. Hypertensive diabetic state was induced with desoxycorticosterone acetate (DOCA) and streptozotocin (STZ) in adult Wistar rats. The rats were divided into 5 groups (n = 5): control group (group 1), hypertensive diabetic (HD) control (group 2), treatment groups receiving LOS + MET (group 3), LOS + GLB (group 4), and LOS + MET + GLB (group 5). Group 1 comprised healthy rats while groups 2-5 were HD rats. The rats were treated orally once daily for 8 weeks. Fasted blood glucose (FBS) level, haemodynamic parameters, and some biochemical indices were thereafter assessed.

RESULTS

FBS level and blood pressure measurements were significantly (P < 0.05) increased following induction by DOCA/STZ. The drug treatment combinations, particularly combination of LOS + MET + GLB, significantly (P < 0.05) reduced the induced hyperglycemia and remarkably decreased systolic blood pressure and heart rate. There was significant (P < 0.05) reduction in raised lactate dehydrogenase and creatinine kinase levels by all drug treatment combinations except LOS + GLB.

CONCLUSIONS

Our findings suggest that LOS combinations with MET and/or GLB exhibited significant antidiabetic and antihypertensive effects against DOCA/STZ-induced hypertensive diabetic state in rats.