Novel effect of adenosine 5'-monophosphate on ameliorating hypertension and the metabolism of lipids and glucose in stroke-prone spontaneously hypertensive rats

Polydatin from Polygoni Cuspidati Rhizoma et Radix regulates glucolipid metabolism in the liver of diabetic rats: Multiscale analysis of network pharmacology and multiomics

BACKGROUND

Polygoni Cuspidati Rhizoma et Radix (Huzhang in Chinese), refers to the root and rhizome of Polygonum cuspidatum Sieb. et Zucc. Huzhang is commonly used in clinical practice for the prevention and treatment of diabetes and its complications, but its active components and regulatory mechanisms have not yet been thoroughly analyzed.

PURPOSE

The network pharmacology combined with multi-omics analysis will be employed to dissect the substance basis and action mechanism of Huzhang in exerting its anti-diabetic activity.

METHODS

This study employed phenotypic indicators for baseline assessment, followed by integrated analysis using network pharmacology, metabolomics, transcriptomics, and qPCR technology to elucidate the active components and pharmacological mechanisms of Huzhang.

RESULTS

The analysis of network pharmacology revealed that polydatin is a potential active component responsible for the anti-T2DM pharmacological effects of Huzhang. In vivo experimental results demonstrated that polydatin significantly regulates blood glucose, lipid levels, liver function, and liver pathological damage in diabetic rats. Analysis results from transcriptomics, metabolomics, and qPCR validation showed that polydatin comprehensively regulates glucose and lipid metabolism in T2DM by modulating bile acid metabolism, fatty acid oxidation, and lipogenesis.

CONCLUSION

Polydatin is a key component of Huzhang in treating T2DM, and its regulatory mechanisms are diverse, indicating significant development potential.

Rhodamine-based fluorescent probe for sequential detection of Al3+ ions and adenosine monophosphate in water

Organic nanoparticles (N1) were prepared by dispersing thiophene-conjugated rhodamine derivative 1 in a buffer solution (10 mM TRIS, pH 7.4, containing 1% DMSO, v/v). N1 selectively recognized Al³⁺ ions through the "OFF-ON" switching mechanism of the spirolactam ring in rhodamine. The resulting N1·Al³⁺ complex recognized the biologically important molecule adenosine monophosphate (AMP) through a cation displacement process with a detection limit of 2 nM. N1 was capable of determining the concentration of Al³⁺ ions in environmental and biological samples. Portable test strips of N1 were prepared for the recognition of Al³⁺ ions and AMP for practical uses. Furthermore, it was demonstrated that the N1·Al³⁺ complex facilitated real-time monitoring of AMP concentration in the hydrolysis of ATP and ADP.

Adenosine and adenosine-5'-monophosphate ingestion ameliorates abnormal glucose metabolism in mice fed a high-fat diet

Background

We have previously reported that ingestion of adenosine (ADN) and adenosine-5′-monophosphate (AMP) improves abnormal glucose metabolism in the stroke-prone spontaneously hypertensive rat model of non-obesity-associated insulin resistance. In this study, we investigated the effect of ADN and AMP ingestion on glucose metabolism in mice with high-fat diet-induced obesity.

Methods

Seven-week-old C57BL/6 J mice were administered distilled water (as a control), 10 mg/L ADN, or 13 mg/L AMP via their drinking water for 14 or 25 weeks, during which they were fed a high-fat diet. Oral glucose tolerance test (OGTT) was conducted on 21-week-old mice fasted for 16 h. Insulin tolerance test (ITT) was performed on 22-week-old mice fasted for 3 h. Blood and muscle were collected for further analysis of serum parameters, gene and protein expression levels, respectively.

Results

Glucose metabolism in the ADN and AMP groups was significantly improved compared with the control. OGTT and ITT showed that ADN and AMP groups lower than control group. Furthermore, phosphorylation of AMP-activated protein kinase (AMPK) and mRNA levels of genes involved in lipid oxidation were enhanced in the skeletal muscle of ADN- and AMP-treated mice.

Conclusion

These results indicate that ingestion of ADN or AMP induces activation of AMPK in skeletal muscle and mitigates insulin resistance in mice with high-fat diet-induced diabetes.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2367-6) contains supplementary material, which is available to authorized users.

Soybean β-conglycinin improves carbohydrate and lipid metabolism in Wistar rats

The effects of dietary soybean β-conglycinin on lipid metabolism and energy consumption were studied in Wistar adult rats. Rats were fed, a diet containing casein (control group) or β-conglycinin (β-conglycinin group), for 4 weeks. Carbohydrate consumption was higher and fat consumption was lower in the β-conglycinin group than in the control group, whereas the total energy consumption was the same between the two groups. Serum adiponectin was higher in the β-conglycinin group than in the control group. Serum triacylglycerol levels in the β-conglycinin group were significantly lower than those in the control group. The secretion rate of triacylglycerols from the liver after the administration of tyloxapol, an inhibitor of lipolysis, was significantly lower in the β-conglycinin group than in the control group. These results suggest the possibility that β-conglycinin exerts hypolipidemic effects through an acceleration in carbohydrate consumption associated with an increase in adiponectin in rats.

Impact of fasting time on hepatic lipid metabolism in nutritional animal studies

Many animal studies on improvement of lipid metabolism, using dietary components, fast the animals on the final day of the feeding. Although fasting has a significant impact on lipid metabolism, its time-dependent influence is not fully understood. We examined the effects of several fasting times on lipid metabolism. Rats fed with a semisynthetic diet for 2 wk were killed after 0 (9:00 am), 6 (7:00 am-1:00 pm), 9 (0:00 am-9:00 am), and 13 h (8:00 pm-9:00 am) of fasting. Compared to the 0 h group, marked reduction of liver weight and hepatic triacylglycerol content was observed in the 9 and 13 h groups. Activities of hepatic enzymes involved in fatty acid synthesis gradually decreased during fasting. In contrast, drastic time-dependent reduction of gene expression, of the enzymes, was observed. Expression of carnitine palmitoyltransferase mRNA was higher in the fasting groups than in the 0 h group. Our study showed that fasting has a significant impact on several parameters related to lipid metabolism in rat liver.

Purinergic signaling and blood vessels in health and disease

Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.

Effects of angiotensin II type 1 receptor blocker and adiponectin on adipocyte dysfunction in stroke-prone spontaneously hypertensive rats

BACKGROUND

Hypoadiponectinemia in lipoatrophy may be related to worsening of hypertension in stroke-prone spontaneously hypertensive rats (SHRSP). One of the beneficial effects of candesartan (Angiotensin II Type 1 receptor blocker) for preventing hypertension may be increasing of adiponectin due to improvement of adipocyte dysfunction. In this study, we determined the effects of candesartan or adiponectin on pathophysiologic features and adipocyte dysfunction in SHRSP.

METHODS

Candesartan was administered to male SHRSP from 16 to 20 weeks of age (2 mg/kg/day). Adiponectin was cloned and intravenously administered to male SHRSP from 16 to 20 weeks of age. We examined biological parameters, as well as the expression and release of adipokines.

RESULTS

The SHRSP exhibited severe atrophy of visceral fat and progression of severe hypertension. The expression and release of leptin and adiponectin were impaired at 6 and 20 weeks of age. Candesartan suppressed the development of lipoatrophy and reduced the incidence of stroke at 20 weeks of age. Candesartan also enhanced the expression of adiponectin and leptin by inducing the overexpression of peroxisome proliferator activated receptor γ. Circulating level of leptin was significantly higher in candesartan group than in the control group, whereas adiponectin was similar in both groups. Intravenous administration of adiponectin resulted in enhancement of adiponectin expression in adipose tissue, but no remarkable effects were found in pathophysiology in SHRSP.

CONCLUSIONS

Our results indicate that candesartan protects against hypertension and adipocyte dysfunction in SHRSP. The induction of leptin expression appeared to be important factor in the inhibition of stroke lesions, whereas adiponectin was not a major regulator of blood pressure in SHRSP with genetic hypertension. Further studies are needed to elucidate the role of the renin-angiotensin system in adipose tissue dysfunction in relation to hypertensive end-organ damage.