Terminalia arjuna bark extract improves diuresis and attenuates acute hypobaric hypoxia induced cerebral vascular leakage

A conjoint analysis of renal structure and omics characteristics reveal new insight to yak high-altitude hypoxia adaptation

BACKGROUND

Yaks have unique adaptive mechanisms to the hypoxic environment, in which the kidney plays an important role. The aim of this study was to explore the histological changes of yak kidney at different altitudes and the metabolites and genes associated with adaptation to the hypoxic environment.

METHODS

We analyzed the tissue structure and transcriptomic metabolomic data of yak kidney tissue at two altitudes, 2600 and 4400 m. We compared and identified the morphological adaptations of the kidney and the metabolites and genes associated with hypoxia adaptation in yaks. Changes in renal morphological adaptations, differential metabolites and genes were compared and identified, combining the two in a joint analysis.

RESULTS

High-altitude yak kidneys showed significant adaptive changes: increased mitochondria, increased glomerular thylakoid area, and decreased localized ribosomes. Transcriptomics and metabolomics identified 69 DAMs (Differential metabolites) and 594 DEGs (differential genes). Functional enrichment analysis showed that the DAMs were associated with protein digestion and absorption, ABC transporter, and MTOR signaling pathway; the DEGs were significantly enriched in Cholesterol metabolism and P53 signaling pathway. The joint analysis indicated that metabolites such as lysine and arginine, as well as key genes such as ABCB5 and COL1A2, were particularly affected under hypoxic conditions, whereas changes in mitochondria in the tissue structure may be related to the expression of MFN1 and OPA1, and changes in glomerular thylakoid membranes are related to VEGFA and TGFB3.

CONCLUSION

The kidney regulates metabolites and gene expression related to hormone synthesis, protein metabolism, and angiogenesis by adjusting the mitochondrial and glomerular thylakoid membrane structure to support the survival of yaks in high-altitude environments.

Potential therapeutic effects of traditional Chinese medicine in acute mountain sickness: pathogenesis, mechanisms and future directions

Background and objectives

Acute mountain sickness (AMS) is a pathology with different symptoms in which the organism is not adapted to the environment that occurs under the special environment of high altitude. Its main mechanism is the organism's tissue damage caused by acute hypobaric hypoxia. Traditional Chinese medicine (TCM) theory focuses on the holistic concept. TCM has made remarkable achievements in the treatment of many mountain sicknesses. This review outlines the pathogenesis of AMS in modern and traditional medicine, the progress of animal models of AMS, and summarizes the therapeutic effects of TCM on AMS.

Methods

Using the keywords "traditional Chinese medicine," "herbal medicine," "acute mountain sickness," "high-altitude pulmonary edema," "high-altitude cerebral edema," "acute hypobaric hypoxia," and "high-altitude," all relevant TCM literature published up to November 2023 were collected from Scopus, Web of Science, PubMed, and China National Knowledge Infrastructure databases, and the key information was analyzed.

Results

We systematically summarised the effects of acute hypobaric hypoxia on the tissues of the organism, the study of the methodology for the establishment of an animal model of AMS, and retrieved 18 proprietary Chinese medicines for the clinical treatment of AMS. The therapeutic principle of medicines is mainly invigorating qi, activating blood and removing stasis. The components of botanical drugs mainly include salidroside, ginsenoside Rg1, and tetrahydrocurcumin. The mechanism of action of TCM in the treatment of AMS is mainly through the regulation of HIF-1α/NF-κB signaling pathway, inhibition of inflammatory response and oxidative stress, and enhancement of energy metabolism.

Conclusion

The main pathogenesis of AMS is unclear. Still, TCM formulas and components have been used to treat AMS through multifaceted interventions, such as compound danshen drip pills, Huangqi Baihe granules, salidroside, and ginsenoside Rg1. These components generally exert anti-AMS pharmacological effects by inhibiting the expression of VEGF, concentration of MDA and pro-inflammatory factors, down-regulating NF-κB/NLRP3 pathway, and promoting SOD and Na + -K + -ATPase activities, which attenuates acute hypobaric hypoxia-induced tissue injury. This review comprehensively analyses the application of TCM in AMS and makes suggestions for more in-depth studies in the future, aiming to provide some ideas and insights for subsequent studies.

Effectiveness of herbal drug Terminalia Arjuna in chronic venous insufficiency - A prospective observational study

INTRODUCTION

Chronic venous insufficiency (CVI) manifests in various clinical presentations ranging from asymptomatic but cosmetic problems to severe symptoms, such as lower limb edema, skin trophic changes, and ulceration. CVI substantially affects the quality of life and work productivity of the patients. Ayurveda, an ancient traditional medicine in India, evaluates the various pathological stages of CVI with a wide range of pathological conditions such as Siragranthi (venous abnormalities), Raktavaritavāta (disorders of vāta occluded by rakta ∼ blood), ApanaVaigunya (vitiated apānavāyu), Arsha (hemorrhoids), VataRakta (rheumatism due to rakta), Kushtha (integumentary disease) and Dushta Vrana (putrefied wound) depending upon the presentations of the patient. Ayurvedic texts mention Terminalia arjuna as a potential herb for treating various conditions related to the circulatory system. The drug is an effective anti-inflammatory, anti-oxidant, and anti-hypertensive and has a definite role in improving cardiovascular hemodynamics and wound healing. These attributes suggest that the potential of Terminalia arjuna needs to be explored as a promising venoactive drug.

METHODS

This prospective observational study included 25 patients (31 limbs) with CVI who were treated with Tab Terminalia arjuna (Bark extract of Terminalia arjuna in a dose of 500 mg, given twice a day) and were observed on two visits on day 30 and day 90. Follow-up was carried out for three months to evaluate post-treatment complications or adverse effects. The clinical outcome assessment was done using Venous Clinical Severity Score (VCSS), and clinical grading was performed using clinical classification (C0 - C6) of CEAP (Clinical-Etiology-Anatomy-Pathophysiology) classification.

RESULTS

The median VCSS score (of both limbs) during the third visit was comparatively lower than the first, with a statistically significant improvement at 0.05 level. Further, there was a substantial positive improvement in the clinical classification of CEAP among the patients in pre and post treatment phase.

CONCLUSION

The prospective observational study shows that Tab Terminalia arjuna is safe and effective in CVI, reducing the symptoms like pain, edema, inflammation, pigmentation, induration and also expediting ulcer healing.

The Diuretic Effects of Coconut Water by Suppressing Aquaporin and Renin–Angiotensin–Aldosterone System in Saline-Loaded Rats

The acute and prolonged diuretic effects of coconut water (CW) and the underlying mechanism were investigated with a saline-loaded rat model. In an acute diuretic experiment, CW could significantly increase urine excretion. In addition, the treatment of CW significantly increased urinary sodium and chloride ions, thereby considerably increasing the excretion of NaCl. However, the calcium concentration and pH value were not affected. In the prolonged diuretic experiment, CW dramatically increased the urine output and urine electrolyte concentrations (Na+, K+, and Cl–). Furthermore, CW could suppress the activation of renin–angiotensin–aldosterone system by decreasing serum antidiuretic hormone, angiotensin II, and aldosterone levels, and significantly increasing the serum atriopeptin level. CW treatment significantly reduced the mRNA expressions and protein levels of aquaporin 1 (AQP1), AQP2, and AQP 3. This report provided basic data for explaining the natural tropical beverage of CW as an alternative diuretic agent.

Preconditioning With Intermittent Hypobaric Hypoxia Attenuates Stroke Damage and Modulates Endocytosis in Residual Neurons

Background: Moderate hypobaric hypoxia induces cerebral ischemic tolerance. We investigated the optimal method for applying hypobaric hypoxia preconditioning at 5,000 m to ischemic brain tissue and combined it with proteomics to determine the mechanisms underlying this effect. Methods: Male SD rats were randomly grouped as S (sham, n = 20), M (middle cerebral artery occlusion [MCAO], n = 28), H2M (intermittent hypobaric hypoxia preconditioned MCAO group, 2 h/day, 10 days, n = 20), H6M (intermittent hypobaric hypoxia preconditioned MCAO group, 6 h/day, 10 days, n = 28), and HpM (persistent hypobaric hypoxia preconditioned MCAO group, 10 days, n = 28). The permanent MCAO model was established based on the Zea Longa method. Infarction was assessed with the modified neurological severity score (mNSS) and 2,3,5-triphenyl tetrazolium chloride staining. The total protein expression of the neuron-specific nuclear protein (NeuN), cysteinyl aspartate specific proteinase 3 (caspase-3), cleaved-caspase-3, and interleukin 6 (IL-6) was determined using western blotting. We assessed the peri-infarct cortex's ultrastructural changes. A label-free proteomic study and western blot verification were performed on the most effective preconditioned group. Results: The H6M group showed a lower infarct volume (p = 0.0005), lower mNSS score (p = 0.0009) than the M group. The H2M showed a lower level of IL-6 (p = 0.0213) than the M group. The caspase-3 level decreased in the H2M (p = 0.0002), H6M (p = 0.0025), and HpM groups (p = 0.0054) compared with that in the M group. Cleaved-caspase-3 expression decreased in the H2M (p = 0.0011), H6M (p < 0.0001), and HpM groups (p < 0.0001) compared with that in the M group. The neurons' ultrastructure and the blood-brain barrier in the peri-infarct tissue improved in the H2M and H6M groups. Immunofluorescence revealed increased NeuN-positive cells in the peri-infarct tissue in the H6M group (p = 0.0003, H6M vs. M). Protein expression of Chmp1a, Arpc5, and Hspa2 factors related to endocytosis were upregulated in the H6M compared with those of the M group (p < 0.05 for all) on western blot verification of label-free proteomics. Conclusions: Intermittent hypobaric hypoxia preconditioning exerts a neuroprotective effect in a rat stroke model. Persistent hypobaric hypoxia stimulation exhibited no significant neuroprotective effect. Intermittent hypoxic preconditioning for 6 h/day for 10 days upregulates key proteins in clathrin-dependent endocytosis of neurons in the cortex.

The chemical profiling of aqueous soluble fraction from Lagopsis supina and its diuretic effects via suppression of AQP and RAAS pathways in saline-loaded rats

ETHNOPHARMACOLOGICAL RELEVANCE

Lagopsis supina (Steph.) Ik. -Gal. ex Knorr. has been widely used as a remedy treatment for diuresis and edema in China over 2500 years. Our previous results showed that the aqueous soluble fraction from L. supina (LSB) possessed acute diuretic effect.

AIM OF THE STUDY

The aim of this study was to appraise the acute (6 h) and prolonged (7 d) diuretic effects, underlying mechanisms, and chemical profiling of LSB.

MATERIALS AND METHODS

The chemical profiling of LSB was performed by ultra-high-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-qTOF-MS/MS). Then, oral administration of LSB (40, 80, 160 and 320 mg/kg) and furosemide (10 mg/kg) once daily for 7 consecutive days to evaluate the diuretic effects in saline-loaded rats. The body weight, food consumption, and water intake were recorded once daily. The urinary volume, pH and electrolyte concentrations (Na+, K+, Cl-, and Ca2+) were measured after administration drugs for acute and prolonged diuretic effects. In addition, the serum levels of Na+-K+-ATPase, angiotensin II (Ang II), anti-diuretic hormone (ADH), aldosterone (ALD), atriopeptin (ANP), aquaporins (AQPs)-1, 2 and 3 were determined by ELISA kits. The mRNA expressions and protein levels of AQPs-1, 2 and 3 were analyzed by real-time quantitative PCR and Western blot assays, respectively.

RESULTS

30 compounds were identified in LSB based on accurate mass and MS/MS fragmentation compared to literature, among which phenylpropanoids and flavonoids could be partly responsible for the major diuretic effect. Daily administration of LSB (160 or 320 mg/kg) prominently increased urinary excretion volume after the 2 h at the first day of treatment, remaining until the 7th day. LSB did not cause Na+ and K+ electrolyte abnormalities, and has minor effect on Cl- and Ca2+ concentrations at 320 mg/kg. Furthermore, LSB observably suppressed renin-angiotensin-aldosterone system (RAAS) activation, including decreased serum levels of Ang II, ADH, and ALD, and prominently increased serum level of ANP in rats. LSB treatment significantly down-regulated the serum levels, mRNA expressions and protein levels of AQP1, AQP2, and AQP3.

CONCLUSION

LSB has a prominent acute and prolonged diuretic effects via suppression of AQP and RAAS pathways in saline-loaded rats, and support the traditional folk use of this plant. Taken together, LSB might be a potential diuretic agent.

Effects of maternal protein restriction on central and peripheral renin-angiotensin systems in male rat offspring

AIMS

We investigated the involvement of the renin angiotensin system (RAS) on the cardiorespiratory control in rats from dams fed with a low-protein diet.

MAIN METHODS

Male offspring were obtained from dams fed a normoprotein diet (NP, 17% casein) and low-protein diet (LP, 8% casein) during pregnancy and lactation. Direct measurements of arterial pressure (AP), heart rate (HR) and respiratory frequency (RF) were recorded in awake 90-day-old at resting and after losartan potassium through either intracerebroventricular (ICV) microinjections or intravenous (IV) administration. Cardiovascular variability was evaluated by spectral analysis. Peripheral chemoreflex sensitivity was assessed through the potassium cyanide (KCN; 40 μg/0.1 ml/rat, IV). Gene expression was evaluated by qPCR, and MAPK (Mitogen Activated Protein Kinase) expression was evaluated by western blot.

KEY FINDINGS

The LP offspring had higher mean AP (MAP) and RF than NP offspring. In the spectral analysis, the LP rats also showed higher low frequency of systolic AP (NP: 2.7 ± 0.3 vs. LP: 5.0 ± 1.0 mmHg). After ICV losartan, MAP and RF in LP rats remained higher than those in NP rats, but without changes in HR. The peripheral chemoreflex was similar between the groups. LP group had lower gene expression of Rac1 (Ras-related C3 botulinum toxin substrate 1) (NP: 1.13 ± 0.06 vs. LP: 0.88 ± 0.08). Peripherally, LP rats had larger delta of MAP after IV losartan (NP: -9.8 ± 2 vs. LP: -23 ± 6 mmHg), without changes in HR and RF.

SIGNIFICANCE

In rats, the RAS participates peripherally, but not centrally, in the maintenance of arterial hypertension in male offspring induced by maternal protein restriction.

Diuretic and Antidiuretic Activities of Ethanol Extract and Fractions of Lagopsis supina in Normal Rats

Lagopsis supina is a well-known traditional Chinese medicine and used as an agent for diuresis in China for centuries. This is the first time to evaluate the diuretic activity of the ethanol extract of L. supina (LS) and its four fractions (LSA, LSB, LSC, and LSD) in normal rats. After the administration of LS-H, LS-M, LSB-H, and LSC-L, the urine output of the rats was significantly increased, while the urine excretion was significantly reduced after treatment with LSB-L. The urine Na+ excretion was remarkably increased with LS-H, LS-M, LSA-H, LSA-L, LSB-H, LSC-L, and LSD-L, and the urine K+ excretion was significantly increased after administration of LS-H and LSB-H. Moreover, the urine Na+ and K+ excretion was significantly reduced after treatment with LSC-H and LSD-H. However, the urine pH values and urine and serum Na+-K+-ATPase levels did not show remarkable change after administration of LS or its four fractions in comparison with the control group. On the contrary, LS and its four fractions can suppress the renin-angiotensin-aldosterone system (RAAS), including ADH arrest by LSB-H, LSB-L, LSC-L, LSD-L, and LSD-H and ALD arrest by LSD-L, as well as promote ANP release by LS-M, LSB-H, LSC-H, and LSD-H, while furosemide can suppress only arrest of ADH within 24 h compared with the control group. In addition, LS and its four fractions did not change the urine and serum TNF-α and IL-6 levels in normal rats within 24 h. This study will provide a quantitative basis for explaining the natural medicinal use of LS as a diuretic agent for edema and promoting the diuretic process.

Lagopsis supina exerts its diuretic effect via inhibition of aquaporin-1, 2 and 3 expression in a rat model of traumatic blood stasis

ETHNOPHARMACOLOGICAL RELEVANCE

Lagopsis supina has been used as a traditional medicinal herb for centuries in China. In folk medicine, it is used for promoting blood circulation and removing blood stasis (PBCRBS), anti-inflammatory and diuretic activities. Modern pharmacological investigation have shown that L. supina have an improvement in blood and lymphatic microcirculation, myocardioprotective, and antioxidative activities. Although the pharmacological research of L. supina was more, there was no report on the diuretic activity.

AIM OF THE STUDY

This study was to evaluate the diuretic activity and the underlying mechanism of an ethanol extract of L. supina (LS) in a rat model of traumatic blood stasis (TBS).

MATERIALS AND METHODS

There were 30 male Sprague-Dawley rats that were randomly assigned to the control group, TBS group, and LS group (10 animals in each group). LS was administered orally (460 mg/kg) once daily for 7 successive days. The control group and TBS group were given an equal amount of 0.3% sodium carboxymethyl cellulose (CMC-Na). For the efficacy evaluation, the urine output volume, the urinary electrolyte concentrations (Na⁺, K⁺, Cl^- and Ca²⁺) and pH value, the levels of angiotensin II (Ang II), atriopeptin (ANP), anti-diuretic hormone (ADH) and aldosterone (ALD), as well as aquaporin (AQP)-1, 2 and 3 protein expressions were detected in a rat model of TBS. The protein expressions of AQP-1, 2 and 3 were detected by quantitative immunohistochemistry (IHC) and Western blot analysis.

RESULTS

In the efficacy evaluation, rat models treated with LS showed a significant increase in the total urine output (p < 0.01). The urinary electrolyte and the acid-base disturbances, including the decrease of Na⁺ and Ca²⁺ levels and the Na⁺/K⁺ value together with the increase in the Cl^- level and the pH value, in the urine of the LS group were compared with the TBS group. Moreover, the levels of Ang II, ADH and ALD of rat model were decreased after being treated with LS (p < 0.05 or p < 0.01), while the ANP level was increased (p < 0.05). In addition, the results of the quantitative IHC and the Western blot analysis showed that the expression levels of AQP-1, 2 and 3 proteins decreased significantly compared with those of the TBS group.

CONCLUSIONS

This is the first reported notable diuretic effect by LS, which probably was through the suppression of the renin-angiotensin-aldosterone system (RAAS) and the regulation of the signaling pathways of AQP-1, 2 and 3 protein expressions. Based on our results, we conclude that L. supina carries out its diuretic effect mainly by down-regulating the levels of AQP-1, 2 and 3 expressions in TBS rat model. These data also embody the traditional Chinese medicine (TCM) application principle of Huo xue li shui. These findings suggest that LS may warrant further evaluation as a possible agent for the diuretic drug in clinical applications. Further research is underway to elucidate the active compounds responsible for the diuretic activity of LS.

Prospective Safety Evaluation of a Cardiovascular Health Dietary Supplement in Adults with Prehypertension and Stage I Hypertension

Objective: To prospectively examine the long-term safety of a cardiovascular health dietary supplement by assessing a comprehensive set of safety measures.

Design: Single-arm, open-label study.

Location: National University of Natural Medicine, Portland, OR.

Subjects: Thirty adults with screening blood pressure readings consistent with prehypertension or stage I hypertension.

Intervention: One caplet per day of a dietary supplement for 6 months. The investigated herbal–mineral supplement contains several ingredients, most notably Rauwolfia serpentina.

Outcome measures: Primary measures included b-type natriuretic peptide (NT-proBNP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), estimated glomerular filtration rate (eGFR), electrolytes, and the Patient Health Questionnaire (PHQ-9). Exploratory measures included physical vital signs, cholesterol levels, high-sensitivity cardiac troponin-I, cystatin C, endothelin, interleukin (IL)-6, IL-17a, tumor necrosis factor-α, high-sensitivity C-reactive protein, blood counts, and the Patient Reported Outcome Measure Information System (PROMIS) Sleep Disturbance Short Form 8b.

Results: NT-proBNP, AST, ALT, eGFR, sodium, calcium, magnesium, PHQ-9 score, and the majority of exploratory measures did not change. However, serum potassium increased (p < 0.05), systolic blood pressure decreased (p < 0.0001), and diastolic blood pressure decreased (p < 0.0001). There were no serious adverse events, but 30% of participants withdrew citing potential side effects, most commonly nasal congestion or fatigue; most participants who reported nasal congestion also reported concomitant seasonal allergies. Adherence to the supplement was 90.9%.

Conclusions: The findings of this study suggest that the investigated dietary supplement is safe for long-term use in adults with prehypertension and stage I hypertension. Additional results of this study, particularly the increase in serum potassium and decreases in systolic and diastolic blood pressure, are promising and suggest that future research on this dietary supplement, or its ingredients, should further explore effects on blood pressure and biologic mechanisms of action, which may involve potassium-sparing and diuretic effects.

Acute and sub-acute toxicological evaluation of lyophilized Nymphaea x rubra Roxb. ex Andrews rhizome extract

Nymphaea x rubra Roxb. ex Andrews (N. rubra) has been widely reported for immunomodulatory properties and treatment of piles, bleeding nose and dysentery in traditional medicinal systems. However, its in-vitro and in-vivo toxicity studies have never been investigated. So, the present study was designed to investigate in-vitro and in-vivo toxicity of methanolic extract of N. rubra rhizome in rats. In-vitro cytotoxicity studies were conducted for different doses of extract in N2a cell lines. For in-vivo toxicity studies, SD rats were divided into three groups and administered with 0, 300 and 2000 mg/kg b. w., p. o., of N. rubra extract respectively. In acute toxicity studies, female animals after extract administration animals were sacrificed for hematological profiling and gross necropsy. In sub-acute toxicity studies, both male and female animals were administered with extract daily for 14 days and were sacrificed for hematological, biochemical and histological examination. Body weight and food water intake was measured daily and animals were observed for visual toxic effects, behavioral changes and mortality. During in-vivo toxicity studies, none of the animals showed signs of toxicity and mortality during toxicity studies. The present findings suggest its safety and NOAEL of N. rubra rhizome extract to be > 2000 mg/kg b. w.