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Stevioside (5-10%) and rebaudioside-A (2-4%) are well-characterized diterpene glycosides found in leaves of Stevia rebaudiana known to have natural sweetening properties with zero glycaemic index. Stevioside has after-taste bitterness, whereas rebaudioside-A is sweet in taste. The ratio of rebaudioside-A to stevioside needs to be changed in order to increase the effectiveness and palatability of this natural sweetener. Plant-specific miRNAs play a significant role in the regulation of metabolic pathways for the biosynthesis of economically important secondary metabolites. In this study inhibition of miRNA through antisense technology was employed to antagonize the repressive action of miRstv_7 on its target mRNAs involved in the steviol glycosides (SGs) biosynthesis pathway. In transgenic plants expressing anti-miRstv_7, reduced expression level of endogenous miRstv_7 was observed than the non-transformed plants. As a result, enhanced expression of target genes, viz. KO (Kaurene oxidase), KAH (Kaurenoic acid-13-hydroxylase), and UGT76G1 (UDP-glycosyltransferase 76G1) led to a significant increase in the rebaudioside-A to stevioside ratio. Furthermore, metabolome analysis revealed a significant increase in total steviol glycosides content as well as total flavonoids content. Thus, our study can be utilized to generate more palatable varieties of Stevia with improved nutraceutical values including better organoleptic and antioxidant properties., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Stevia rebaudiana (stevia) contains commercially important steviol glycosides, stevioside and rebaudioside A, these compounds have insulinotropic and anti-hyperglycemic effect. Steviol, stevioside and rebaudioside-A have taste modulation and insulin potentiation activity. Stevia leaves are composed of steviol (2-5%), stevioside (4-13%) and rebaudioside-A (1-6%). Stevioside has after-taste bitterness, rebaudioside-A is sweetest in taste among all the glycosides present. Therefore, lower ratio of rebaudioside-A to stevioside has bitter after-taste, which makes stevia plants unpalatable. By over-expressing the genes, SrUGT76G1 and SrKO, we propose to increase the ratio of RebA to stevioside in stevia. Various lines were generated and amongst them, seven lines had both the transgenes present. Co-overxpresion of SrUGT76G1 and SrKO led to the increased concentration of RebA in all the seven transgenic lines (KU1-KU7) than control plant and RebA to stevioside ratio also increased significantly. Steviol, stevioside and RebA showed a differential concentration in all the seven lines, but the pattern was the same in all of them and the ratio of RebA to stevioside increased dramatically. In transgenic line 2 (KU2), RebA showed a steep increase in concentration 52% the rebaudioside-A to stevioside ratio increased from 0.74 (control) to 2.83. In overall all the lines, RebA showed a positive correlation with steviol and stevioside. Overexpression of SrKO led to an increase in steviol which increased the stevioside, overexpression of SrUGT76G1 ultimately increased RebA concentration. In conclusion, concentration of RebA increased significantly with co- overexpression of SrUGT6G1 and SrKO genes. Lines with increased RebA are more palatable and commercially viable., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Nasrullah et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Treatment of Ischemic Stroke is inordinately challenging due to its complex aetiology and constraints in shuttling therapeutics across blood-brain barrier. Ropinirole hydrochloride (Rp), a propitious neuroprotectant with anti-oxidant, anti-inflammatory, and anti-apoptotic properties (3A) is repurposed for remedying ischemic stroke and reperfusion (I/R) injury. The drug's low bioavailability in brain however, limits its therapeutic efficacy. The current research work has reported sub-100 nm gamma-L-Glutamyl-L-Cysteine coated Human Serum Albumin nanoparticles encapsulating Rp (C-Rp-NPs) for active targeting in ischemic brain to encourage in situ activity and reduce unwanted toxicities. Confocal microscopy and brain distribution studies confirmed the enhanced targeting potentiality of optimized C-Rp-NPs. The pharmacokinetics elucidated that C-Rp-NPs could extend Rp retention in systemic circulation and escalate bioavailability compared with free Rp solution (Rp-S). Additionally, therapeutic assessment in transient middle cerebral occlusion (tMCAO) model suggested that C-Rp-NPs attenuated the progression of I/R injury with boosted therapeutic index at 1000 times less concentration compared to Rp-S via reinstating neurological and behavioral deficits, while reducing ischemic neuronal damage. Moreover, C-Rp-NPs blocked mitochondrial permeability transition pore (mtPTP), disrupted apoptotic mechanisms, curbed oxidative stress and neuroinflammation, and elevated dopamine levels post tMCAO. Thus, our work throws light on fabrication of rationally designed C-Rp-NPs with enormous clinical potential., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Farhan Jalees Ahmad has patent #202111059333 pending to Jamia Hamdard., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The therapeutic efficacy of Artemisia annua L. is governed by artemisinin (ART), prevalently produced by A. annua extraction. Due to the modest amount of ART (0.01-1 %dw) in this plant, commercialization of ACTs is difficult. In this study, the floral-dip based transformation protocol for A. annua was developed to enhance expression of artemisinin biosynthesis genes and ART content. For dipping, the effective infiltration media components were optimized, and to obtain high transformation (26.9%) partially open bud stage capitulum of floral development was used. Hygromycin phospho-transferase ( hptII ) selection marker was used to validate the transformed T 1 progenies. The copy numbers of the transgene ( hptII ) in T 1 progenies were determined using a sensitive, high-throughput SYBR Green based quantitative RT-PCR. The results of the hptII transgene were compared with those of the low copy number, internal standard ( hmgr ). Using optimised PCR conditions, one, two and three transgene copies in T 1 transformants were achieved., Competing Interests: The authors declare that they have no conflict of interest., (© 2022 The Authors. Published by Elsevier B.V.)

With the advent of modern lifestyles, diabetes-related comorbidities attributed the importance of low-caloric natural sweetener plants such as Stevia rebaudiana . This plant is the viable source of steviol glycosides (SGs) and other economically important secondary metabolites. Glandular trichomes (GTs) play the role as a reservoir for all secondary products present in the plant species. Therefore, the present study was carried out to evaluate the influence of different plant growth regulators (PGRs) on GT density and its impact on the SG content. The direct shoot regeneration system was developed on Murashige and Skoog (MS) + benzyl aminopurine (BAP) (1.0 mg/L) + naphthaleneacetic acid (NAA) (0.5 mg/L), and MS + BAP (1.5 mg/L) + NAA (0.5 mg/L) from nodal and leaf explants, respectively. Among the combination of PGRs used, MS medium fortified with BAP (1.0 mg/L) and 2,4-dichlorophenoxyacetic acid (2,4-D) (0.5 mg/L) played a significant role in increasing the GT density on leaf and stem tissues of S. rebaudiana . Furthermore, high-performance thin-layer chromatography and gas chromatography-mass spectrophotometry data confirmed a notable rise in SGs and other valuable secondary metabolites. Thus, the protocol developed can be used for the propagation of stevia with an improved metabolic profile at a large scale., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Amongst the various diseases on a global scale, the second leading cause of mortality and morbidity is ischemic stroke due to the unavailability of an effective therapy. With the growing occurrence and its related health risks along with the absence of effective therapeutics, ischemic stroke demands the continued and intensive research to explore effective and safe therapeutics. These therapies may positively affect the numerous pathways associated with neuroprotection, thus, extending the advantages to a larger population of stroke patients. Several preclinical studies employing neuroprotectants have shown promising outcomes, but failed in clinical trials either because of the lack of safety or efficacy. The Blood-Brain Barrier (BBB) restricts the delivery of various potent neuroprotectants to the specific areas of the brain. The application of nanovehicles for the delivery of drugs in the brain, however, could revolutionize the treatment of ischemic stroke. These nanovehicles loaded with the drug could readily traverse the BBB via carrier, receptor and adsorptive-mediated endocytosis into the brain without compromising the integrity of the BBB. Recent advances in neuronanotherapeutics have resulted in improved neuronal regeneration and recovery after ischemic stroke. In this review, we have attempted to discuss unexploited neuronanotherapeutics potentials to treat and manage ischemic stroke., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)