The protective effects of gallic acid and SGK1 inhibitor on cardiac damage and genes involved in Ca2+ homeostasis in an isolated heart model of ischemia/reperfusion injury in rat

Serum and glucocorticoid-induced kinase 1 (SGK1) is an enzyme that may play a vital role in myocardial ischemia/reperfusion (I/R) injury. This enzyme may affect sarcoplasmic reticulum Ca2+ ATPase (SERCA2), ryanodine receptor (RyR2) and sodium/calcium exchanger (NCX1) during myocardial ischemia/reperfusion injury. The objective of this investigation was to analyze the effects of the combination of GSK650394 (SGK1 inhibitor) and gallic acid on the calcium ions regulation, inflammation, and cardiac dysfunction resulting from ischemia/reperfusion (I/R) injury in the heart. Sixty male Wistar rats were randomly divided into six groups, pretreated with gallic acid or vehicle for 10 days. Then the heart was isolated and exposed to I/R. In the SGK1 inhibitor groups, GSK650394 was infused 5 min before ischemia induction. After that, Ca2+ homeostasis, inflammatory factors, cardiac function, antioxidant activity, and myocardial damage were evaluated. The findings suggested that the use of two drugs in combination therapy produced more significant improvements in left ventricular end diastolic pressure, left ventricular systolic pressure, RR-interval, ST-elevation, inflammation factors, and antioxidant enzymes activity as compared to the use of each drug. Despite this, there was a significant decrease observed in heart marker enzymes (including lactate dehydrogenase (LDH), troponin-I (cTn-I), creatine kinase-MB (CK-MB) and creatine phosphokinase (CPK) when compared to the ischemic group. Additionally, the expression of RyR2, NCX1, and SERCA2 genes showed a noteworthy increase as compared to the ischemic group. The findings of this study propose that using both of these agents on myocardial I/R injury could have superior advantages compared to using only one of them.

Gentisic acid ameliorates type 2 diabetes induced by Nicotinamide-Streptozotocin in male mice by attenuating pancreatic oxidative stress and inflammation through modulation of Nrf2 and NF-кB pathways

AIMS

There is a close link between oxidative stress, inflammation, and type 2 diabetes mellitus (T2DM). Gentisic acid (GA) is a di-phenolic compound and an active metabolite of aspirin that possesses antioxidant and anti-inflammatory properties, but its potential anti-diabetic effects have not been evaluated so far. Therefore, this study aimed to evaluate GA's potential antidiabetic effects through the Nuclear Factor Erythroid 2-Related Factor (Nrf2) and Nuclear Factor Kappa Beta (NF-кB) signaling pathways.

MATERIAL AND METHODS

In this study, T2DM induced by a single intraperitoneal injection of STZ (65 mg/kg B.W) after 15 min nicotinamide (120 mg/kg B.W) injection. After seven days of injections, fasting blood glucose (FBS) was measured. Seven days after FBS monitoring treatments started. Grouping and treatments were as follows: 1) Normal control group; NC, 2) Diabetic control group; DC, 3) Metformin group; MT (150 mg/kg B.W, daily), 4) Test group; GA (100 mg/kg B.W, daily). Treatments continued for 14 consecutive days.

KEY FINDINGS

Diabetic mice treatment with GA significantly decreased FBS, improved plasma lipid profiles and pancreatic antioxidant status. GA modulated Nrf2 pathway by upregulation of Nrf2 protein, NAD(P)H: quinone oxidoreductase 1 (Nqo1), and p21, and downregulation of miR-200a, Kelch-like ECH-associated protein 1 (Keap1), and nicotinamide adenine dinucleotide phosphate oxidase-2 (NOX2). Also, GA attenuated inflammation by upregulation of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) and interleukin-10 (IL-10) and downregulation of miR-125b, NF-кB, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1ß).

SIGNIFICANCE

GA attenuates T2DM, possibly by improving antioxidant status through the Nrf2 pathway and attenuation of inflammation.

Gentisic acid protects against diabetic nephropathy in Nicotinamide-Streptozotocin administered male mice by attenuating oxidative stress and inflammation: The role of miR-200a/Keap1/Nrf2 pathway, renin-angiotensin system (RAS) and NF-кB

Oxidative stress and inflammation play a pivotal role in the pathogenesis of diabetic nephropathy (DN). Local renin-angiotensin systems (RAS) contribute to the pathogenesis and progression of DN by exacerbating oxidative stress and inflammation.Gentisic acid (GA), a phenolic compound and also a metabolite of aspirin, is reported to possess antioxidant and anti-inflammatory properties. However, the protective effects of GA against DN remain to be elucidated. Nicotinamide (110 mg/kg) and streptozotocin (65 mg/kg) were used to induce diabetes in male mice. Oral administration of GA once daily for 2 weeks (100 mg/kg) ameliorated diabetes-induced renal injury by reducing plasma creatinine, urea, blood urea nitrogen, and urinary albuminuria levels. Diabetic mice showed a significant increase in total oxidant status and malondialdehyde, along with decreased catalase, superoxide dismutase, and glutathione peroxidase in the kidney tissue, which was ameliorated in the GA-treated mice. Histopathological analysis showed that GA treatment reduced diabetes-induced renal injury. Furthermore, GA treatment was associated with the downregulation of miR-125b, nuclear factor kappa beta (NF-кB), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and upregulation of interleukin-10 (IL-10), miR-200a, and nuclear factor erythroid 2-related factor 2 (Nrf2) in the renal tissue. GA treatment also downregulated angiotensin-converting enzyme 1 (ACE1), angiotensin II receptor 1 (AT1R), and NADPH oxidase 2 (NOX 2) and upregulated angiotensin-converting enzyme 2 (ACE2). In conclusion, the ameliorative effects of GA against DN may be attributed to its powerful antioxidant and anti-inflammatory properties through the downregulation of NF-кB, upregulation of Nrf2, and modulation of RAS in renal tissue.

Hepatoprotective effects of gentisic acid through its anti-oxidant properties in nicotinamide-streptozotocin induced diabetic mice

Objectives

Type 2 diabetes mellitus (T2DM) is a common metabolic disorder that causes many complications. Liver failure is one of the complications of T2DM. Oxidative stress plays a major role in the development and progression of T2DM-induced liver injury. Gentisic acid (GA) is a metabolite of aspirin and also a phenolic compound found in natural sources that is a highly effective antioxidant and free radical scavenger. So, in this study, the potential preventive benefits of GA against liver damage induced by T2DM were explored.

Materials and Methods

This study was conducted on 24 adult male mice. T2DM was induced by intraperitoneal injection of a single dose of streptozotocin (at a dose of 65 mg/kg), 15 min after the injection of nicotinamide (at a dose of 120 mg/kg). The grouping was as follows: 1) Normal Control Group; 2) Diabetic Control Group; 3) Positive Control Group: received metformin (150 mg/kg body weight daily) through gavage; 4) Treatment Group: received GA at the dose of 100 mg/kg body weight daily through gavage. Treatments continued for two weeks.

Results

Two weeks of GA treatment in diabetic mice reduced fasting blood glucose, improved plasma levels of hepatic enzymes, and increased liver tissue antioxidant capacity. Histopathological examination revealed that GA administration reduced diabetes-induced liver damage. Furthermore, GA treatment led to the down-regulation of Kelch-like ECH-associated protein 1 (Keap1) and up-regulation of nuclear factor E2-related factor 2 (Nrf2).

Conclusion

The results of this study showed that GA exerts hepatoprotective effects in STZ-induced T2DM mice.

Sodium Hydrosulfide Modification of Mesenchymal Stem Cell-Exosomes Improves Liver Function in CCL4-Induced Hepatic Injury in Mice

Background

Liver diseases and injuries are important medical problems worldwide. Acute liver failure (ALF) is a clinical syndrome characterized by severe functional impairment and widespread death of hepatocytes. Liver transplantation is the only treatment available so far. Exosomes are nanovesicles originating from intracellular organelles. They regulate the cellular and molecular mechanisms of their recipient cells and have promising potential for clinical application in acute and chronic liver injuries. This study compares the effect of Sodium hydrosulfide (NaHS) modified exosomes with non-modified exosomes in CCL4-induced acute liver injury to ascertain their role in ameliorating hepatic injury.

Methods

Human Mesenchymal stem cells (MSCs) were treated with or without NaHS (1 μmol) and exosomes were isolated using an exosome isolation kit. Male mice (8-12 weeks old) were randomly divided into four groups (n=6): 1-control, 2-PBS, 3- MSC-Exo, and 4- H2S-Exo. Animals received 2.8 ml/kg body weight of CCL4 solution intraperitoneally, and 24 h later MSC-Exo (non-modified), H2S-Exo (NaHS-modified), or PBS, was injected in the tail vein. Moreover, 24 h after Exo administration, mice were sacrificed for tissue and blood collection.

Results

Administration of both MSC-Exo and H2S-Exo reduced inflammatory cytokines (IL-6, TNF-α), total oxidant levels, liver aminotransferases, and cellular apoptosis.

Conclusion

MSC-Exo and H2S-Exo had hepato-protective effects against CCL4-induced liver injury in mice. Modification of cell culture medium with NaHS as an H2S donor enhances the therapeutic effects of MSC exosomes.