Olmesartan Medoxomil, An Angiotensin II-Receptor Blocker, Ameliorates Renal Injury In db/db Mice

From Hypertension to Beyond: Unraveling the Diverse Mechanisms of Olmesartan in Disease Modulation

Olmesartan, originally known for its antihypertensive properties, exhibits promising potential in addressing inflammation-mediated diseases. As an angiotensin II receptor blocker (ARB), Olmesartan influences pivotal pathways, including reactive oxygen species, cytokines, NF-κB, TNF-α, and MAPK. This suggests a viable opportunity for repurposing the drug in conditions such as ulcerative colitis, neuropathy, nephropathy, and cancer, as supported by multiple preclinical studies. Ongoing clinical trials, particularly in cardiomyopathy and nephropathy, suggest a broader therapeutic scope for Olmesartan. Repurposing efforts would entail comprehensive investigations using disease-specific preclinical models and dedicated clinical studies. The drug's established safety profile, wide availability, and well-understood ARB mechanism of action offer distinct advantages that could facilitate a streamlined repurposing process. In summary, Olmesartan's versatile impact on inflammation-related pathways positions it as a promising candidate for repurposing across various diseases. Ongoing clinical trials and the drug's favorable attributes enhance its appeal for further exploration and potential application in diverse medical contexts.

Diabetic Nephropathy: Pathogenesis to Cure

Diabetic nephropathy (DN) is a leading cause of end-stage renal disorder (ESRD). It is defined as the increase in urinary albumin excretion (UAE) when no other renal disease is present. DN is categorized into microalbuminuria and macroalbuminuria. Factors like high blood pressure, high blood sugar levels, genetics, oxidative stress, hemodynamic and metabolic changes affect DN. Hyperglycemia causes renal damage through activating protein kinase C (PKC), producing advanced end glycation products (AGEs) and reactive oxygen species (ROS). Growth factors, chemokines, cell adhesion molecules, inflammatory cytokines are found to be elevated in the renal tissues of the diabetic patient. Many different and new diagnostic methods and treatment options are available due to the increase in research efforts and progression in medical science. However, until now, no permanent cure is available. This article aims to explore the mechanism, diagnosis, and therapeutic strategies in current use for increasing the understanding of DN.

The Treatment Effectiveness Evaluation for Slowing the Progression of Diabetic Nephropathy During Stage 4 Chronic Kidney Disease

INTRODUCTION

People with advanced diabetic nephropathy (DN) are at high risk for development of end-stage renal disease (ESRD) or death. Whether renin-angiotensin system inhibitors and some concomitant drugs could still continue to delay the onset of ESRD in the later stage of DN needs to be clarified. This study aimed to evaluate the relationship of the therapeutic methods as well as clinicopathologic variables with prognosis of patients with biopsy-proven DN during stage 4 of chronic kidney disease (CKD).

METHODS

Forty-six DN patients who underwent renal biopsy in stage 4 CKD were enrolled from January 1, 2002, to December 31, 2019. Clinical data were abstracted retrospectively from the time of renal biopsy. Follow-up data were collected until April 1, 2020, or from the day of renal biopsy to either the occurrence of ESRD or death. The primary outcome was the composite of ESRD or death. Treatment effectiveness and the prognostic ability of clinicopathologic data were evaluated using multivariate Cox regression analyses.

RESULTS

The median renal survival duration was 17.3 (95% confidence interval, 7.4-27.3 months). Primary endpoint events occurred in 29 individuals (63.0%) during follow-up, including 24 who reached ESRD and 5 who died before progression to ESRD. None of the clinicopathologic data, including pathologic cass of DN, were statistically independent prognostic factors for renal survival. Conventional therapies, such as use of renin-angiotensin system (RAS) inhibitors, a level of glycated hemoglobin (HbA1c) < 7%, and blood pressure < 130/80 mmHg, were also not statistically different between the stable and progressive groups.

CONCLUSION

Specific therapies including targeting blood pressure < 130/80 mmHg, HbA1c concentration < 7%, and use of RAS inhibitors could not effectively delay the onset of ESRD in the later stage of DN. Therefore, efforts to slow the progression of DN should focus on early diagnosis and treatment.

Novel antihypertensive action of rutin is mediated via inhibition of angiotensin converting enzyme/mineralocorticoid receptor/angiotensin 2 type 1 receptor (ATR1) signaling pathways in uninephrectomized hypertensive rats

Hypertension is the most common cardiovascular disease that affects approximately 26% of adult population, worldwide. Rutin is one of the important flavonoids that is consumed in the daily diet, and found in many food items, vegetables, and beverages. Uninephrectomy (UNX) of the left kidney was performed, followed by induction of hypertension. The rats were randomly divided into four groups of 10 rats: group 1-Sham-operated rats; group 2-UNX rats, group 3-UNX-L-NAME (40 mg/kg) plus rutin (100 mg/kg bwt), and groups 4-UNX-L-NAME plus lisinopril (10 mg/kg bwt), orally for 3 weeks. Results revealed significant heightening of arterial pressure and oxidative stress indices, while hypertensive rats treated with rutin had lower expressions of angiotensin converting enzyme (ACE) and mineralocorticoid receptor in uninephrectomized rats. Together, rutin as a novel antihypertensive flavonoid could provide an unimaginable benefits for the management of hypertension through inhibition of angiotensin converting enzyme and mineralocorticoid receptor. PRACTICAL APPLICATIONS: Hypertension has been reported to be the most common cardiovascular disease, affecting approximately 26% of the adult population worldwide with predicted prevalence to increase by 60% by 2025. Recent advances in phytomedicine have shown flavonoids to be very helpful in the treatment of many diseases. Flavonoids have been used in the treatment and management of cardiovascular diseases, obesity and hypertension. The study revealed that rutin, a known flavonoid inhibited angiotensin converting enzyme (ACE), angiotensin 2 type 1 receptor (ATR1), and mineralocorticoid receptor (MCR), comparable to the classic ACE inhibitor, Lisinopril, indicating the novel antihypertensive property of rutin. Therefore, flavonoids such as rutin found in fruits and vegetables could, therefore, serve as an antihypertensive drug regimen. Combining all, functional foods rich in flavonoids could be used as potential therapeutic candidates for managing uninephrectomized hypertensive patients.

The Influence of Hypertensive Therapies on Circulating Factors: Clinical Implications for SCFAs, FGF21, TNFSF14 and TNF-α

Studying the role of circulatory factors in the pathogenesis of diseases has been key to the development of effective therapies. We sought to examine the effect of antihypertensive therapies on numerous circulatory factors including short chain fatty acids and growth factors in a human cohort. A subset of participants from an earlier study was characterized by their hypertensive and/or treatment status and separated into three groups: (i) normotensives; (ii) untreated hypertensive and (iii) treated hypertensive subjects. Circulating levels of short chain fatty acids, FGF21 and TNF superfamily members were measured as part of this study. Both F2-isoprostane and circulating lipid levels were reanalysed as part of this current study. We found that antihypertensive treatment increased butyrate levels and decreased acetate levels to levels similar to normotensives. We also found that antihypertensive treatments reduced levels of circulating FGF21, TNFSF14 and TNF-α. In conclusion, we identified several circulatory factors that are altered in hypertension.

Oxymatrine Inhibits Twist-Mediated Renal Tubulointerstitial Fibrosis by Upregulating Id2 Expression

The final pathway for the development of diabetic nephropathy (DN) into chronic renal failure in DN is glomerulosclerosis and tubulointerstitial fibrosis. Renal tubular lesions can occur in the early stage of DN renal injury. Cumulative evidence shows that oxymatrine (OMT) has a variety of biological and pharmacological properties. In recent years, more attention has been paid on the preventive and therapeutic influence of OMT on organ fibrosis. In this experiment, db/db mice were intraperitoneally injected with OMT 120 mg/kg for 8 weeks, and NRK-52E cultured with 30 mmol/L glucose and 0.1 mg/mL OMT for 48-hour. We investigated the relationship between Id2 and Twist in NRK-52E cells and the effect of OMT on the expression of E-cadherin, α-SMA, Fibronectin, and Collagen-IV by Western blot, Real-time PCR, Immunofluorescence, cell transfection, Co-Immunoprecipitation, and Luciferase assays. OMT increased the expression of Id2 but decreased that of Twist under high glucose condition in vitro and in vivo. The promoted recovery of Id2 facilitated its binding to Twist and affected E-cadherin activity inhibiting EMT and the excessive proliferation and abnormal deposition of ECM. In brief, OMT promotes Id2 to reverse EMT and exert anti-fibrotic effect in diabetic renal tubular epithelial cells by binding Id2 to Twist and affecting its transcriptional activation of downstream target genes. Or findings provide a new experimental basis for delaying the progress and for treatment of diabetic renal fibrosis.