Genistein alleviates renin-angiotensin system mediated vascular and kidney alterations in renovascular hypertensive rats

Combination of α-Klotho and telmisartan attenuates diabetic kidney disease via mitigating EMT, inflammation and apoptosis

Diabetic kidney disease (DKD) remains a leading cause of end-stage kidney disease worldwide, necessitating novel therapeutic approaches. This study investigated the renoprotective potential of recombinant human α-Klotho (α-Klotho; KL) as an adjunctive therapy to telmisartan (TEL) in streptozotocin-induced DKD rats and high glucose and exogenous TGF-β1 (rh-TGF-β1) -exposed NRK-52E cells. The combination therapy significantly preserved kidney function parameters, including reduced blood urea nitrogen, serum creatinine, and kidney weight/body weight ratio compared to monotherapy or untreated DKD groups. Histopathological analyses revealed that the combination therapy markedly ameliorated glomerular hypertrophy, tubular atrophy, and interstitial fibrosis as evidenced by H&E, PAS, and Masson's trichrome staining. Immunohistochemical evaluation demonstrated significant downregulation of AT1R and TGF-β1 expression in the combination group. In-vitro studies confirmed that co-treatment enhanced cell viability and preserved normal epithelial morphology of NRK-52E cells under high glucose conditions. Mechanistically, the combination therapy modulated the apoptotic pathway by upregulating Bcl-2 and downregulating Bax expression while simultaneously reducing phosphorylated NF-κB levels, suggesting suppression of inflammation-mediated tubular apoptosis. Additionally, the combination therapy effectively reduced extracellular matrix (ECM) deposition by decreasing fibronectin levels (ELISA) and collagen expressions (RT-PCR). Immunofluorescence analysis demonstrated reduced vimentin expression, indicating a lower degree of epithelial-mesenchymal transition (EMT), along with an increase in α-SMA levels in the animal tissues. These findings demonstrate that adjunctive α-Klotho therapy with telmisartan exerts synergistic renoprotective effects through anti-fibrotic, anti-inflammatory, and anti-apoptotic mechanisms. This combination approach represents a promising therapeutic strategy for DKD management that warrants further clinical investigation.

Apitherapy for drug-induced kidney disease: a narrative review on its mechanisms

OBJECTIVES

The use of medications for the treatment of various diseases often results in kidney damage. Apitherapy is a natural therapeutic tool with potential utility for this purpose. This narrative review analyzes and summarizes the scientific evidence on the use of apitherapy in drug-induced kidney disease.

CONTENT

This review summarizes and analyzes recent advances in drug-induced kidney disease and explores, based on the available scientific evidence, how apitherapy can modify these mechanisms and be utilized for prevention and treatment.

SUMMARY

Apitherapy (the complementary and integrative use of beehive products) is a potentially useful therapeutic system for the treatment of various diseases. This review examines the preclinical and clinical evidence available regarding its potential use in drug-induced kidney disease.

OUTLOOK

Apitherapy has effects on various pathophysiological mechanisms of drug-induced kidney disease, including oxidative stress, inflammation, decreased renal blood flow, glomerular damage, increased membrane permeability, activity of the renin-angiotensin-aldosterone axis, mitochondrial dysfunction, and apoptosis. Further studies in humans are needed to evaluate its efficacy in the clinical setting, but the available evidence is promising.

Cannabis sativa L. Leaf Oil Displays Cardiovascular Protective Effects in Hypertensive Rats

Hemp (Cannabis sativa L.) leaf oil (HLO) contains several bioactive compounds such as phenolics, flavonoids, and quercetin. However, the effects of HLO on hypertensive conditions have not yet been investigated. This study investigated the cardiovascular protective effects of HLO in a nitric oxide (NO) synthase inhibitor-induced hypertensive rat model. Five weeks of HLO administration significantly prevented blood pressure elevation, improved cardiac function, and mitigated cardiac hypertrophy. Furthermore, HLO ameliorated vascular dysfunction by reducing sympathetic nerve stimulation-induced vasoconstriction, increasing endothelium-dependent vasorelaxation, as well as decreasing vascular wall thickness and vascular smooth muscle cell proliferation. HLO inhibited renin-angiotensin system (RAS) activation and downregulated angiotensin II type 1 (AT1) receptor and NADPH oxidase expression. Additionally, HLO normalized the circulating NO metabolites, decreased oxidative stress, and enhanced antioxidant status. These findings suggest that HLO protects against cardiovascular dysfunction and preserves its morphology. The mechanism of action might involve the suppression of RAS overactivity and oxidative stress through the Ang II/AT1 receptor/NOX2 pathway in NO-deficient hypertension.

Mechanism Actions of Coniferyl Alcohol in Improving Cardiac Dysfunction in Renovascular Hypertension Studied by Experimental Verification and Network Pharmacology

Renovascular hypertension (RH), a secondary hypertension, can significantly impact heart health, resulting in heart damage and dysfunction, thereby elevating the risk of cardiovascular diseases. Coniferol (CA), which has vascular relaxation properties, is expected to be able to treat hypertension-related diseases. However, its potential effects on cardiac function after RH remain unclear. In this study, in combination with network pharmacology, the antihypertensive and cardioprotective effects of CA in a two-kidney, one-clip (2K1C) mice model and its ability to mitigate angiotensin II (Ang II)-induced hypertrophy in H9C2 cells were investigated. The findings revealed that CA effectively reduced blood pressure, myocardial tissue damage, and inflammation after RH. The possible targets of CA for RH treatment were screened by network pharmacology. The interleukin-17 (IL-17) and tumor necrosis factor (TNF) signaling pathways were identified using a Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The inflammatory response was identified using a Gene Ontology (GO) enrichment analysis. Western blot analysis confirmed that CA reduced the expression of IL-17, matrix metallopeptidase 9 (MMP9), cyclooxygenase 2 (COX2), and TNF α in heart tissues and the H9C2 cells. In summary, CA inhibited cardiac inflammation and fibrohypertrophy following RH. This effect was closely linked to the expression of MMP9/COX2/TNF α/IL-17. This study sheds light on the therapeutic potential of CA for treating RH-induced myocardial hypertrophy and provides insights into its underlying mechanisms, positioning CA as a promising candidate for future drug development.

Pharmacological effects of MT-1207 in bilateral renal artery stenosis hypertension and its hypotensive targets validation

MT-1207 (MT) as a new antihypertensive drug is under clinical trial. However, its hypotensive mechanism has not been experimentally explored, and it is unknown whether MT can be used for bilateral renal artery stenosis hypertension. Using two-kidney two-clip (2K2C) to mimic bilateral renal artery stenosis in rats, a stroke-prone renovascular hypertension model, the present study further verified its antihypertensive effect, cardiovascular and renal protection, mortality reduction and lifespan prolongation, as well as demonstrated its two novel pharmacological effects for uric acid-lowering and cognition-improving. Notably, MT did not aggravate renal dysfunction; instead, it had beneficial effects on reducing serum uric acid level and maintaining serum K+ at a relatively stable level in 2K2C rats. In contrast, angiotensin receptor blocker losartan aggravated renal dysfunction in 2K2C rats. Mechanistically, MT hypotensive effect was dependent on its blockade of α1 and 5-HT2 receptors, since MT pretreatment abolished these receptor agonists-induced blood pressure elevations in vivo. Further evidence showed MT bound to and interacted with these receptor subtypes including α1A, α1B, α1D, 5-HT2A, 5-HT2B, and 5-HT2C receptors known for control of blood pressure. In conclusion, MT may be used for treatment of bilateral renal artery stenosis hypertension, different from losartan that is prohibited for treatment of bilateral renal artery stenosis hypertension. Targets validation of MT hypotensive mechanism and beneficial effects of MT on uric acid and cognitive function provide new insights for this novel multitarget drug, deserving clinical trial attention.

Kaempferol protects against cardiovascular abnormalities induced by nitric oxide deficiency in rats by suppressing the TNF-α pathway

Kaempferol is a natural flavonoid compound that exhibits various pharmacological actions. However, there are few reports regarding the role of kaempferol in cardiovascular abnormalities. This study aimed to assess whether kaempferol could prevent cardiovascular malfunction and hypertrophy provoked by chronic inhibition of nitric oxide (NO) formation in rats. Rats (180-200 g) were treated daily with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) (40 mg/kg, in drinking water) for five weeks concomitant with kaempferol (oral administration) at a dose of 20 mg/kg or 40 mg/kg or lisinopril (5 mg/kg). Kaempferol partially prevented the progression of hypertension provoked by NO inhibition (p < 0.05). Left ventricular malfunction and hypertrophy present in hypertensive rats were alleviated by concurrent administration of kaempferol (p < 0.05). Furthermore, L-NAME rats had increased sympathetic nerve-mediated vasoconstriction and decreased acetylcholine-induced vasorelaxation and aortic wall thickening, which were resolved by kaempferol treatment (p < 0.05). Kaempferol restored tissue superoxide formation, malondialdehyde, catalase activity, plasma nitric oxide metabolites, tumor necrosis factor-alpha (TNF-α) and interleukin-6 in L-NAME rats (p < 0.05). Overexpression of tumor necrosis factor receptor 2 (TNFR2), phosphatidylinositol 3-kinases (PI3K), AKT serine/threonine kinase 1 (Akt1) and smad2/3 in heart tissue and upregulation of tumor necrosis factor receptor 1 (TNFR1), phosphorylated nuclear factor-kappaB (p-NF-κB) and transforming growth factor beta 1 (TGF-β1) in vascular tissue were suppressed by kaempferol (p < 0.05). In conclusion, kaempferol exerts antihypertensive, cardioprotective, antioxidant, and anti-inflammatory effects in NO-dependent hypertensive rats. The underlying mechanisms of kaempferol in preventing cardiovascular changes induced by L-NAME were due to the suppression of the TNF-α pathway.

Natural angiotensin converting enzyme inhibitors: A safeguard against hypertension, respiratory distress syndrome, and chronic kidney diseases

Hypertension is a serious concern as it is one of the causes of kideny failure and pulmonary fibrosis. An important therapeutic strategy for treating chronic hypertension is to inhibit the angiotensin converting enzyme (ACE). ACE inhibition reduces kidney damage, pulmonary artery pressure, and high blood pressure. Due to their high efficacy and low risk of side effects, natural renin-angiotensin system inhibitors have drawn increasing attention over the past decades. Alkaloids, amino acids, anthocyanidins, flavonoids, glucosinolates, isoflavonoids, phenolic acids, polyphenolics, and triterpenoids are among the bioactive metabolites pocessing an impressive ACE inhibitory activity. Many herbs including Rosmarinus officinalis, Hibiscus sabdariffa, Curcuma longa, Rauwolfia serpentina, Emblica officinalis, Cynara scolymus, Punica granatum, Mucuna pruriens, Capsicum annuum, and Moringa olifera were found having ACE inhibitory activities comparable to captopril and enalpril. These enticing natural ACE inhibitors deserve to be a safeguard medicine against hypertension, respiratory distress syndrome, and chronic kidney diseases. More clinical trials are required before new natural compounds and herbs can be used to treat chronic hypertension and its ramifications, such as respiratory distress syndrome and kidney failure.

(Poly)phenols and the regulation of NADPH oxidases

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs) are enzymes that generate superoxide anion (O2•-) and hydrogen peroxide (H2O2), and that are widely distributed in mammalian tissues. Many bioactives, especially plant (poly)phenols are being studied for their capacity to regulate NOXs. The modulation of these enzymes are of central relevance to maintain redox homeostasis and regulate cell signaling. In in vitro and ex vivo assays, and in experimental animal models, different (poly)phenols are able to modulate NOX-dependent generation of O2•- and H2O2. Mechanistically, most of the known effects of (poly)phenols and of their metabolites on NOX1, NOX2, and NOX4, include the modulation of: i) the expression of the different constituent subunits, and/or ii) posttranslational modifications involved in the assembly and translocation of the protein complexes. Very limited evidence is available on a direct action of (poly)phenols on NOX active site (electron-transferring protein). Moreover, it is suggested that the regulation by (poly)phenols of systemic events, e.g. inflammation, is frequently associated with their capacity to regulate NOX activation. Although of physiological significance, more studies are needed to understand the specific targets/mechanisms of NOX regulation by (poly)phenols, and the (poly)phenol chemical structures and moieties directly involved in the observed effects. It should be kept in mind the difficulties of NOX's studies associated with the complexity of NOXs biochemistry and the methodological limitations of O2•- and H2O2 the determinations. Studies relating human ingestion of specific (poly)phenols, with NOX activity and disease conditions, are guaranteed to better understand the health importance of (poly)phenol consumption and the involvement of NOXs as biological targets.

Research Progress of Flavonoids Regulating Endothelial Function

The endothelium, as the guardian of vascular homeostasis, is closely related to the occurrence and development of cardiovascular diseases (CVDs). As an early marker of the development of a series of vascular diseases, endothelial dysfunction is often accompanied by oxidative stress and inflammatory response. Natural flavonoids in fruits, vegetables, and Chinese herbal medicines have been shown to induce and regulate endothelial cells and exert anti-inflammatory, anti-oxidative stress, and anti-aging effects in a large number of in vitro models and in vivo experiments so as to achieve the prevention and improvement of cardiovascular disease. Focusing on endothelial mediation, this paper introduces the signaling pathways involved in the improvement of endothelial dysfunction by common dietary and flavonoids in traditional Chinese medicine and describes them based on their metabolism in the human body and their relationship with the intestinal flora. The aim of this paper is to demonstrate the broad pharmacological activity and target development potential of flavonoids as food supplements and drug components in regulating endothelial function and thus in the prevention and treatment of cardiovascular diseases. This paper also introduces the application of some new nanoparticle carriers in order to improve their bioavailability in the human body and play a broader role in vascular protection.

Cardiovascular complications are resolved by tuna protein hydrolysate supplementation in rats fed with a high-fat diet

This study is aimed to investigate whether tuna protein hydrolysate (TPH) supplementation could alleviate cardiovascular complications induced by a high-fat diet (HFD) in rats. Rats were fed a HFD for 16 weeks and given TPH (100 mg/kg, 300 mg/kg, or 500 mg/kg) or metformin (100 mg/kg) (n = 8) for the last four weeks. TPH had the following effects: resolved their impaired glucose tolerance, hyperglycemia, dyslipidemia, obesity, and hypertension (p < 0.05); alleviated left ventricular dysfunction and hypertrophy (p < 0.05), and vascular dysfunction and hypertrophy (p < 0.05); adipocyte hypertrophy; increases in circulating leptin and tumor necrosis factor (TNF-α) were mitigated (p < 0.05); increased renin-angiotensin system (RAS), oxidative stress, and decreased nitric oxide metabolites were modulated (p < 0.05). TPH restored the expression of angiotensin II receptor type 1 (AT1R)/NADPH oxidase 2 (NOX2), endothelial nitric oxide synthase (eNOS), nuclear factor erythroid 2-related factor (Nrf2)/heme oxygenase-1 (HO-1), and peroxisome proliferator-activated receptor γ (PPARγ)/the nuclear factor kappa B (NF-κB) protein in cardiovascular tissue (p < 0.05). In metabolic syndrome (MS) rats, metformin and TPH had comparable effects. In conclusion, TPH alleviated cardiovascular complications related to MS. It suppressed RAS, oxidative stress, and inflammation that were associated with modulation of AT1R/NOX2, eNOS, Nrf2/HO-1, and PPARγ/NF-κB expression.

Mitigation effect of galangin against aortic dysfunction and hypertrophy in rats with metabolic syndrome

Vascular alterations induced by a high-fat diet (HFD) are involved in the development of hypertension. Galangin, a flavonoid, is the major active compound isolated from galangal and propolis. The objective of this study was to investigate the effect of galangin on aortic endothelial dysfunction and hypertrophy, and the mechanisms involved in HFD-induced metabolic syndrome (MS) in rats. Male Sprague-Dawley rats (220-240 g) were separated into three groups: control + vehicle, MS + vehicle, and MS + galangin (50 mg/kg). Rats with MS received HFD plus 15% fructose solution for 16 weeks. Galangin or vehicle was orally administered daily for the final four weeks. Galangin reduced body weight and mean arterial pressure in HFD rats (p < 0.05). It also reduced circulating fasting blood glucose, insulin, and total cholesterol levels (p < 0.05). Impaired vascular responses to the exogenous acetylcholine observed in the aortic ring of HFD rats were restored by galangin (p < 0.05). However, the response to sodium nitroprusside did not differ between the groups. Galangin enhanced the expression of the aortic endothelial nitric oxide synthase (eNOS) protein and increased circulating nitric oxide (NO) levels in the MS group (p < 0.05). Aortic hypertrophy in HFD rats was alleviated by galangin (p < 0.05). Increases in tumour necrosis factor-alpha (TNF-α), interleukin (IL)-6 levels, angiotensin-converting enzyme activity and angiotensin II (Ang II) concentrations in rats with MS were suppressed in galangin treated group (p < 0.05). Furthermore, galangin reduced the upregulation of angiotensin II type I receptor (AT1R) and transforming growth factor-beta (TGF-β) expression in rats with MS (p < 0.05). In conclusion, galangin alleviates metabolic disorders and improves aortic endothelial dysfunction and hypertrophy in the MS group. These effects were consistent with increased NO availability, reduced inflammation, and suppressing Ang II/AT1R/TGF-β signalling pathway.

Genistein attenuates renal ischemia-reperfusion injury via ADORA2A pathway

BACKGROUND

Studies have shown oxidative stress and apoptosis are the main pathogenic mechanisms of renal ischemia/reperfusion (IR) injury (IRI). Genistein, a polyphenolic non-steroidal compound, has been extensively explored in oxidative stress, inflammation and apoptosis. Our research aims to reveal the potential role of genistein on renal IRI and its potential molecular mechanism both in vivo and in vitro.

METHODS

In vivo experiments, mice were pretreated with or without genistein. Renal pathological changes and function, cell proliferation, oxidative stress and apoptosis were measured. In vitro experiments, overexpression of ADORA2A and knockout of ADORA2A cells were constructed. Cells proliferation, oxidative stress and apoptosis were analyzed.

RESULTS

Our results in vivo showed that the renal damage induced by IR was ameliorated by genistein pretreatment. Moreover, ADORA2A was activated by genistein, along with inhibition of oxidative stress and apoptosis. The results in vitro showed that genistein pretreatment and ADORA2A overexpression reversed the increase of apoptosis and oxidative stress in NRK-52E cells induced by H/R, while the knockdown of ADORA2A partially weakened this reversal from genistein treatment.

CONCLUSIONS

Our results demonstrated that genistein have a protective effect against renal IRI by inhibiting oxidative stress and apoptosis via activating ADORA2A, presenting its potential use for the treatment of renal IRI.

Plant Flavonoids on Oxidative Stress-Mediated Kidney Inflammation

The kidney is susceptible to reactive oxygen species-mediated cellular injury resulting in glomerulosclerosis, tubulointerstitial fibrosis, tubular cell apoptosis, and senescence, leading to renal failure, and is a significant cause of death worldwide. Oxidative stress-mediated inflammation is a key player in the pathophysiology of various renal injuries and diseases. Recently, flavonoids' role in alleviating kidney diseases has been reported with an inverse correlation between dietary flavonoids and kidney injuries. Flavonoids are plant polyphenols possessing several health benefits and are distributed in plants from roots to leaves, flowers, and fruits. Dietary flavonoids have potent antioxidant and free-radical scavenging properties and play essential roles in disease prevention. Flavonoids exert a nephroprotective effect by improving antioxidant status, ameliorating excessive reactive oxygen species (ROS) levels, and reducing oxidative stress, by acting as Nrf2 antioxidant response mediators. Moreover, flavonoids play essential roles in reducing chemical toxicity. Several studies have demonstrated the effects of flavonoids in reducing oxidative stress, preventing DNA damage, reducing inflammatory cytokines, and inhibiting apoptosis-mediated cell death, thereby preventing or improving kidney injuries/diseases. This review covers the recent nephroprotective effects of flavonoids against oxidative stress-mediated inflammation in the kidney and their clinical advancements in renal therapy.

Nobiletin resolves left ventricular and renal changes in 2K-1C hypertensive rats

This study investigated the effects of nobiletin on cardiorenal changes and the underlying mechanisms involved in two-kidney, one-clip (2K-1C) hypertension. 2K-1C rats were treated with nobiletin (15 or 30 mg/kg/day) or losartan (10 mg/kg/day) for 4 weeks (n = 8/group). Nobiletin (30 mg/kg) reduced high levels of blood pressure and circulating angiotensin II and angiotensin-converting enzyme activity in 2K-1C rats. Left ventricular (LV) dysfunction and remodelling in 2K-1C rats were alleviated in the nobiletin-treated group (P < 0.05). Nobiletin reduced the upregulation of Ang II type I receptor (AT₁R)/JAK (Janus kinase)/STAT (signal transducer and activator of transcription) protein expression in cardiac tissue of 2K-1C rats (P < 0.05). The reduction in kidney function, and accumulation of renal fibrosis in 2K-1C rats were alleviated by nobiletin (P < 0.05). Overexpression of AT₁R and NADPH oxidase 4 (Nox4) protein in nonclipped kidney tissue was suppressed in the nobiletin-treated group (P < 0.05). The elevations in oxidative stress parameters and the reductions in antioxidant enzymes were attenuated in 2K-1C rats treated with nobiletin (P < 0.05). In summary, nobiletin had renin-angiotensin system inhibitory and antioxidant effects and attenuated LV dysfunction and remodelling via restoration of the AT₁R/JAK/STAT pathway. Nobiletin also resolved renal damage that was related to modulation of the AT₁R/Nox4 cascade in 2K-1C hypertension.