The role of nanomaterials in enhancing natural product translational potential and modulating endoplasmic reticulum stress in the treatment of ovarian cancer.

Ovarian cancer, and particularly its most frequent type, epithelial ovarian carcinoma, constitutes one of the most dangerous malignant tumors among females. Substantial evidence has described the potential of phytochemicals against ovarian cancer. The effect of natural compounds on endoplasmic reticulum (ER) stress is of great relevance in this regard. In ovarian cancer, the accumulation of misfolded proteins in the ER lumen results in decompensated ER stress. This leads to deregulation in the physiological processes for the posttranslational modification of proteins, jeopardizes cellular homeostasis, and increases apoptotic signaling. Several metabolites and metabolite extracts of phytochemical origin have been studied in the context of ER stress in ovarian cancer. Resveratrol, quercetin, curcumin, fucosterol, cleistopholine, fucoidan, and epicatechin gallate, among others, have shown inhibitory potential against ER stress. The chemical structure of each compound plays an important role concerning its pharmacodynamics, pharmacokinetics, and overall effectiveness. Studying and cross-comparing the chemical features that render different phytochemicals effective in eliciting particular anti-ER stress actions can help improve drug design or develop multipotent combination regimens. Many studies have also investigated the properties of formulations such as nanoparticles, niosomes, liposomes, and intravenous hydrogel based on curcumin and quercetin along with some other phytomolecules in ovarian cancer. Overall, the potential of phytochemicals in targeting genetic mechanisms of ovarian cancer warrants further translational and clinical investigation.

Natural Products for the Management of Castration-Resistant Prostate Cancer: Special Focus on Nanoparticles Based Studies.

Prostate cancer is the most common type of cancer among men and the second most frequent cause of cancer-related mortality around the world. The progression of advanced prostate cancer to castration-resistant prostate cancer (CRPC) plays a major role in disease-associated morbidity and mortality, posing a significant therapeutic challenge. Resistance has been associated with the activation of androgen receptors via several mechanisms, including alternative dehydroepiandrosterone biosynthetic pathways, other androgen receptor activator molecules, oncogenes, and carcinogenic signaling pathways. Tumor microenvironment plays a critical role not only in the cancer progression but also in the drug resistance. Numerous natural products have shown major potential against particular or multiple resistance pathways as shown by in vitro and in vivo studies. However, their efficacy in clinical trials has been undermined by their unfavorable pharmacological properties (hydrophobic molecules, instability, low pharmacokinetic profile, poor water solubility, and high excretion rate). Nanoparticle formulations can provide a way out of the stalemate, employing targeted drug delivery, improved pharmacokinetic drug profile, and transportation of diagnostic and therapeutic agents via otherwise impermeable biological barriers. This review compiles the available evidence regarding the use of natural products for the management of CRPC with a focus on nanoparticle formulations. PubMed and Google Scholar search engines were used for preclinical studies, while ClinicalTrials.gov and PubMed were searched for clinical studies. The results of our study suggest the efficacy of natural compounds such as curcumin, resveratrol, apigenin, quercetin, fisetin, luteolin, kaempferol, genistein, berberine, ursolic acid, eugenol, gingerol, and ellagic acid against several mechanisms leading to castration resistance in preclinical studies, but fail to set the disease under control in clinical studies. Nanoparticle formulations of curcumin and quercetin seem to increase their potential in clinical settings. Using nanoparticles based on betulinic acid, capsaicin, sintokamide A, niphatenones A and B, as well as atraric acid seems promising but needs to be verified with preclinical and clinical studies.

Unleashing the Potential of Microbial Natural Products in Drug Discovery: Focusing on Streptomyces as Antimicrobials Goldmine.

The natural product specialized metabolites produced by microbes and plants are the backbone of our current drugs. Ironically, we are in a golden age of understanding natural product biosynthesis, biochemistry, and engineering. These advances have the potential to usher in a new era of natural product exploration and development, taking full advantage of the unique and favorable properties of natural product compounds in drug discovery. There is now an increasing realization that these privileged structures represent the optimal starting point for the development of clinically viable assets. Here, we outline the current state-of-the-art in antimicrobial natural product drug discovery, specifically Streptomyces species, with a specific focus on how the emerging field of synthetic biology is delivering the tools and technologies required to unlock the therapeutic potential of natural products. We illustrate how these approaches are circumventing many of the problems that have historically plagued conventional screening programs, enabling the expedient discovery of new molecules with novel functions.

Chemical Characterization and Anti-Inflammatory Activity of Phytoconstituents from Swertia alata.

Swertia alata C.B Clarke (Gentianaceae) is a well-reported plant in the traditional system of medicine. The present study was intended to isolate the phytoconstituents from the ethanolic extract of the aerial parts of S. alata; and evaluate for in vitro COX-1/COX-2 inhibition activity, in vivo anti-inflammatory and ulcerogenic activity. Phytoisolation involved partitioning of S. alata ethanolic extract into petroleum ether and chloroform soluble fractions using silica gel-based column chromatography. The isolation afforded two phytoisolates, namely oleanolic acid (SA-1) and 3-hydroxylup-12-(13)-ene-17-carboxylic acid (SA-4). Phytoisolates structures were established by melting point, ultraviolet (UV), attenuated total reflection-Fourier-transform infrared (ATR-FTIR), nuclear magnetic resonance (1H-NMR, 13C-NMR and HMBC) and mass spectrometry. Phytoisolates were further evaluated for in vitro cyclooxygenase (COX-1/COX-2) inhibitory activity, in vivo anti-inflammatory and ulcerogenic activity. The study revealed SA-4 (COX-1/COX-2 inhibition activity of 104/61.68 µM with % inhibition of 61.36) to be more effective than SA-1 (COX-1/COX-2 inhibition activity of 128.4/87.25 µM, with % inhibition of 47.72). SA-1 and SA-4, when subjected to ulcerogenic study, exhibited significant gastric tolerance. The current study reports chromatographic isolation and spectrometric characterization of SA-1 and SA-4. The present study concludes that compound SA-4 possess significant anti-inflammatory activity and less irritant property over gastric mucosa with no significant ulcerogenicity in comparison to indomethacin.

Nanophytomedicine Based Novel Therapeutic Strategies in Liver Cancer.

Liver cancer is the fifth (6.3% of all cancers i.e., 548,000 cases/year) and ninth (2.8% of all cancers i.e., 244,000 cases/year) most prevalent cancer worldwide in men and women, respectively. Although multiple choices of therapies are offered for Hepatocellular Carcinoma (HCC) like liver resection or transplant, radiofrequency ablation, transarterial chemoembolization, radioembolization, and systemic targeted agent, by the time of diagnosis, most of the cases of HCC are in an advanced stage, which renders therapies like liver transplant or resection and local ablation impractical; and targeted therapy has its shortcomings like general toxicity, imprecise selectivity, several adversative reactions, and resistance development. Therefore, novel drugs with specificity and selectivity are needed to provide the potential therapeutic response. Various researches have shown the potential of phytomedicines in liver cancer by modulating cell growth, invasion, metastasis, and apoptosis. However, their therapeutic potential is held up by their unfavorable properties like stability, poor water solubility, low absorption, and quick metabolism. Nonetheless, the advancement of nanotechnology-based innovative nanocarrier formulations has improved the phytomedicines' profile to be used in the treatment of liver cancer. Nanocarriers not only improve the solubility and stability of phytomedicines but also extend their residence in plasma and accomplish specificity. In this review, we summarize the advancements introduced by nanotechnology in the treatment of liver cancer. In particular, we discuss quite a few applications of nanophytomedicines like curcumin, quercetin, epigallocatechin-3-gallate, berberine, apigenin, triptolide, and resveratrol in liver cancer treatment.