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Climate change and human activities severely impact the viability of plants and ecosystems, threatening the environment, biodiversity, and the sustainable development of plant-based products. Biotic and abiotic (ecosystem) determinants affect species distribution and long-term survival, which in turn influence the quality of plants used as herbal medicines and other high-value products. In recent decades, diverse anthropogenic impacts have significantly affected these quality aspects. Climate change, excessive plant exploitation, habitat loss, species vulnerability, and other factors have adversely affected the growth, reproduction, and adaptation of species populations, as well as the quality and volume of primary plant materials supplied to pharmaceutical markets. Despite these growing challenges, there is limited knowledge of potential strategies to prevent or mitigate these impacts, particularly for vulnerable species collected from the wild or harvested from traditional production systems. Hence, effective strategies for preserving and increasing plant populations are urgently needed. In this study, we propose a new framework including the main sustainability factors to better understand and address the vulnerability of a species, hence mitigate the impact of climate change. We assess the applicability of our proposed framework via seven case studies of vulnerable species (i.e., Aquilaria malaccensis Lam., Boswellia sacra Flück., Crocus sativus L., Panax quinquefolius L., Pilocarpus microphyllus Stapf ex Wardlew., Rhodiola rosea L., and Warburgia salutaris (G.Bertol.) Chiov.) from main biogeographic realms, all widely used as medicinal plants. These species present various challenges related to the sustainability of their use, impacting their current and future status locally and globally. Their economic importance, combined with rising demands and specific risks of overexploitation, are also key factors considered here. The suggested framework for the sustainability of medicinal and other high-value plant-based products in the phytopharmaceutical industry emphasises strategies that promote conservation and sustainable resource use. It can also be adapted for other vulnerable species requiring urgent attention. [ABSTRACT FROM AUTHOR]

Background: Sarcocephalus pobeguinii (Hua ex Pobég) is used in folk medicine to treat oxidative-stress related diseases, thereby warranting the investigation of its anticancer and anti-inflammatory properties. In our previous study, the leaf extract of S. pobeguinii induced significant cytotoxic effect against several cancerous cells with high selectivity indexes towards non-cancerous cells. Aim: The current study aims to isolate natural compounds from S. pobeguinii, and to evaluate their cytotoxicity, selectivity and anti-inflammatory effects as well as searching for potential target proteins of bioactive compounds. Methods: Natural compounds were isolated from leaf, fruit and bark extracts of S. pobeguinii and their chemical structures were elucidated using appropriate spectroscopic methods. The antiproliferative effect of isolated compounds was determined on four human cancerous cells (MCF-7, HepG2, Caco-2 and A549 cells) and non-cancerous Vero cells. Additionally, the anti-inflammatory activity of these compounds was determined by evaluating the nitric oxide (NO) production inhibitory potential and the 15-lipoxygenase (15-LOX) inhibitory activity. Furthermore, molecular docking studies were carried out on six putative target proteins found in common signaling pathways of inflammation and cancer. Results: Hederagenin (2), quinovic acid 3-O-[α-D-quinovopyranoside] (6) and quinovic acid 3-O-[β-D-quinovopyranoside] (9) exhibited significant cytotoxic effect against all cancerous cells, and they induced apoptosis in MCF-7 cells by increasing caspase-3/-7 activity. (6) showed the highest efficacy against all cancerous cells with poor selectivity (except for A549 cells) towards noncancerous Vero cells; while (2) showed the highest selectivity warranting its potential safety as a chemotherapeutic agent. Moreover, (6) and (9) significantly inhibited NO production in LPS-stimulated RAW 264.7 cells which could mainly be attributed to their high cytotoxic effect. Besides, the mixture nauclealatifoline G and naucleofficine D (1), hederagenin (2) and chletric acid (3) were active against 15-LOX as compared to quercetin. Docking results showed that JAK2 and COX-2, with the highest binding scores, are the potential molecular targets involved in the antiproliferative and anti-inflammatory effects of bioactive compounds. Conclusion: Overall, hederagenin (2), which selectively killed cancer cells with additional anti-inflammatory effect, is the most prominent lead compound which may be further investigated as a drug candidate to tackle cancer progression. [ABSTRACT FROM AUTHOR]

This study determines the phytochemical contents of selected medicinal plant extracts quantitatively using spectrophotometry and to evaluate their safety on mammalian cells in vitro using tetrazolium-based colorimetric cytotoxicity assay. Twenty-two ethanolic plant extracts were assessed, and the result showed that Psidium guajava had the highest concentration of alkaloids (219.06±11.50mg/g dry-weight (dw)). In contrast, Acacia nilotica leaf extract with 191.60±9.07mg/gdw had the highest level of flavonoids. Vernonia amygdalina and Moringa oleifera contained more steroids than the other plant extracts while condensed tannin was highest in Carya illinoinensis (21.72 ± 0.84 mg/g dw). Coffea arabica, Acacia nilotica leaf, Vernonia amygdalina, Carya illinoinensis and Psidium guajava had more saponins than the other plant extracts. Regarding cytotoxicity evaluation, Allium cepa and Tulbaghia violacea with concentration killing 50% of cells (LC50) values of 0.5182±0.40 and 0.4909 ± 0.034 mg/ml, respectively, were the safest of all the plant extracts. Acacia nilotica pod and Camelia japonica leaf extracts were the most cytotoxic with LC50 values of 0.0101 ± 0.016 and 0.0151 ± 0.005 mg/ml, respectively, which are well below the recommended toxic cut-off point (0.03mg/ml). The best selectivity index (SI) value of 1.061 was obtained with Aloe ferox against S. aureus, which is a Gram-positive bacterium. [ABSTRACT FROM AUTHOR]

Selenium (Se) plays an important role for many organisms as an essential trace element nutrient. Its biological effects comprise mainly incorporation into the structure of selenoproteins, which are involved in cell activation, proliferation and differentiation in innate and adaptive immunity. Additionally, Se demonstrates antioxidant and anticancer potential at optimal doses. Furthermore, sulfur (S)-containing compounds have considerable promise regarding antimicrobial and anticancer drug development, in addition to the area of green and ecofriendly pesticides. Nitric oxide (NO) is known as a pro-inflammatory mediator associated with various physiological processes and plays an important role in the immune response. Regarding primary metabolites, water-soluble sugars and organic acids affect the taste and other organoleptic properties of fruits and vegetables such as color, flavor and aroma. The aim of the present study was to investigate the influence of Se and S enrichment on antibacterial and cytotoxicity activities, NO inhibition and further changes in primary metabolism in multi-leaf green (V1) and red (V2) lettuce. The plants were treated with three levels of Se via foliar application in the presence of three S levels in the nutrient solution under greenhouse conditions. The authors tested the hypothesis that the 'crosstalk' between Se and S can affect antibacterial activity, cytotoxicity and NO inhibition in lettuce plants under Se and S enrichment. Additionally, Se and S have a unique effect on soluble sugars and organic acids biosynthesis. The results indicated that extracts of the treated green and red multi-leaf lettuce were not cytotoxic to Vero kidney cells at the highest concentration tested of 1 mg/mL. The acetone extract of red lettuce had antibacterial activity against Pseudomonas aeruginosa with minimum inhibitory concentration (MIC) of 0.156 and 0.625 µg/mL under S2/Se1 and S2/Se2 treatments, respectively. Extracts of both previous treatments were active against Staphylococcus aureus and Escherichia coli with MIC = 1.25 µg/mL. As with antibacterial activity, the acetone extract of green (V1) and red (V2) lettuce treated with higher S (S2) under Se-limiting condition produced the best NO inhibition with IC50 = 97 µg/mL. Moreover, the red cultivar (V3) exhibited NO inhibition with IC50 = 113 and 130 µg/mL in response to S1/Se2 and S2/Se2 treatments, respectively. Under higher S and Se-limiting condition in the green and red multi-leaf lettuce, the levels of glucose and fructose increased therein to 125.0±0.36 and 94.8±1.6 mg g-1 DM, respectively, whereas in the red lettuce subjected to higher S and low Se (Se1) fertilization, the glucose level significantly increased to 89.3±0.37 mg g-1 DM. Under higher S and Se conditions (Se2/S2) glucose level in green and red lettuce enhanced dramatically (80.8±0.25 and 75.4±1.4 mg g-1 DM, respectively) in comparison to Se0/S0, Se1/S1, Se2/S1 treatments, but did not show significant changes between both cultivars. The elevated Se and S treatments (Se2/S2) accumulated more fructose in red lettuce (66.1±0.6 mg g-1 DM) than the green one (53.9±1.5 mg g-1 DM). Apart from watersoluble sugars malic acid accumulated in red lettuce under Se and S treatments, however its concentration remained unaltered among all treatments. While in green lettuce a synergistic interaction between Se and S revealed a dramatic decline in malic acid level from (15.3 ±0.86 mg g-1 DM) under Se and S-limiting condition to 11.0±0.74 and 6.64±0.43 mg g-1 DM in response to Se1/S1 and Se2/S2 treatments, respectively. Collectively, the findings indicate that Se and S enrichment evoked antibacterial and NO inhibitory activities. Additionally, Se/S crosstalk showed both antagonistic and synergistic effects on the biosynthesis of soluble sugars and organic acids and have great effects on the final nutritional value and quality of lettuce plants. [ABSTRACT FROM AUTHOR]

Apoptosis of germ cells is an important feature of spermatogenesis, as this process allows the removal of excess germ cells from testicular tissue. This is crucial to control the number of germ cells that can be supported and nourished by the Sertoli cells. It has been established that up to 75 % of germ cells are lost during the development of spermatogonia. In this process, germ cells with defective genes are removed. Also, apoptosis regulates homeostasis of testicular tissue by maintaining a balance between germ cell proliferation and cell death. This is necessary as it guarantees normal spermatogenesis. Apoptosis also occurs during maturation divisions of spermatocytes and spermatids but albeit to a lesser extent. Several factors, known pro-apoptotic proteins, play a critical role in the process of apoptosis. The most vital pro-apoptotic proteins are caspase-3, B-cells lymphoma 2 (Bcl2), truncated BH3 interacting death domain (tBID), tumor suppressor protein (p53), and Bcl-2 associated protein (BAX). Execution of apoptosis may be triggered by either an extrinsic or an intrinsic pathway. The extrinsic pathway is initiated by death receptors and death ligands. Death receptors trigger pro-apoptotic proteins such as caspase-3 for the execution of apoptosis. The intrinsic pathway, on the other hand, is triggered by nutrient deprivation, stress, or DNA damage, which in turn activates Bcl2 families of pro-apoptotic proteins that foster apoptosis. The present review focuses on pro-apoptotic proteins and their mechanisms of action, with special emphasis on their involvement in germ cell apoptosis in the testicular tissues of mammalian and avian species., Competing Interests: Declaration of Competing Interest The authors declare that there are no competing interests., (Copyright © 2022 Elsevier B.V. All rights reserved.)