Syringa microphylla Diels: A comprehensive review of its phytochemical, pharmacological, pharmacokinetic, and toxicological characteristics and an investigation into its potential health benefits

Antibacterial effect and mechanisms of action of forsythoside B, alone and in combination with antibiotics, against Acinetobacter baumannii and Pseudomonas aeruginosa

BACKGROUND

Antibiotic resistance complicates infection treatments. Natural products, such as phenylethanoid glycosides, including forsythoside B (FB), are gaining attention in clinical use as alternative treatments, either alone or in combination with antibiotics.

PURPOSE

To investigate the antibacterial effects and mechanisms of FB alone and in combination with antibiotics against Acinetobacter baumannii and Pseudomonas aeruginosa.

METHODS

To elucidate the underlying antibacterial mechanism of FB, we assessed intracellular ATP concentration, pH levels, membrane potential, and cell membrane integrity. We also observed bacterial morphology and conducted biofilms eradication assay. FB toxicity was evaluated using the cell counting kit-8 assay. The in vivo pharmacodynamics of FB was explored using a P. aeruginosa systemic infection mouse model. The study also examined the potential synergistic effects of FB with commonly used antibiotics by the checkerboard dilution method and time-kill assay.

RESULTS

The findings indicate that the mechanism of antibacterial activity of FB is through the disruption of bacterial cell membranes, thereby increasing cell membrane permeability, particularly in gram-negative bacteria. Synergistic effects of FB combined with meropenem were demonstrated against resistant strains. FB demonstrated low toxicity in both in vitro and in vivo models, supporting its safety and efficacy for use alone or as an antibiotic adjuvant.

CONCLUSIONS

FB expands the antibacterial spectrum and enhances the effectiveness of existing antibiotics against resistant bacterial strains, making it a promising adjuvant for treating gram-negative bacterial infections. This study highlights the potential of FB in combating antibiotic resistance and suggests further research into its mechanisms and drug development applications. It provides a framework for studying the interaction between natural products and microorganisms, revealing new biological mechanisms.

Echinacoside inhibits hepatocellular carcinoma progression by targeting the miR-30c-5p/FOXD1/KLF12 axis

BACKGROUND

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-attributed mortality and the primary liver malignancy in the world. Echinacoside is a phenylethanoid glycoside derived from traditional Chinese medicinal herbs which possessed multiple health benefits on humans, including anti-tumor effects.

OBJECTIVE

This study aimed to demonstrate the function of echinacoside in HCC progression and the involvement of miR-30c-5p/FOXD1/KLF12 axis.

METHODS

The HepG2 cells were treated by different dose of echinacoside, miR-30c-5p mimic, miR-30c-5p inhibitor, and FOXD1 overexpression lentiviruses or siRNA individually or simultaneously. The cell invasion and migration were measured by transwell assay. RNA and protein levels were tested by RT-PCR and western blot, respectively. The regulatory function of miR-30c-5p on Forkhead box D1 (FOXD1), FOXD1 on Krüppel-like factor 12 (KLF12) was tested by luciferase reporter assay or/and ChIP assay. Meanwhile, a liver cancer lung metastasis mice model was used to examine the functions of echinacoside and miR-30c-5p on HCC metastasis in vivo. Moreover, the correlations among miR-30c-5p, FOXD1, KLF12, and HCC prognosis was analyzed using clinical sample and TCGA database.

RESULTS

Based on both in vitro and in vivo investigations, we found that echinacoside could inhibit HCC cell migration, invasiveness, and tumor metastasis, and associated with the enhanced miR-30c-5p/FOXD1/KLF12 axis. Furthermore, through analyzing the interactions among intermediate molecules, we revealed that miR-30c-5p, FOXD1, and KLF12üere clinically relevant with each other in HCC patients, correlated with HCC prognosis, and regulated by echinacoside to contribute in the inhibition of HCC progression.

CONCLUSIONS

These findings suggest that echinacoside could inhibit HCC progression, and the mechanism related to the enhanced miR-30c-5p/FOXD1/KLF12 axis. Moreover, the abovementioned intermediate molecules might serve as prospective biomarkers for HCC prognosis.

Therapeutic potential of plant iridoids in depression: a review

CONTEXT

Depression is a mental disorder characterized by low mood, reduced interest, impaired cognitive function, and vegetative symptoms such as sleep disturbances or poor appetite. Iridoids are the active constituents in several Chinese classical antidepressant formulae such as Yueju Pill, Zhi-Zi-Hou-Po Decoction, Zhi-Zi-Chi Decoction, and Baihe Dihuang Decoction. Parallel to their wide usages, iridoids are considered potential lead compounds for the treatment of neurological diseases.

OBJECTIVE

The review summarizes the therapeutic potential and molecular mechanisms of iridoids in the prevention or treatment of depression and contributes to identifying research gaps in iridoids as potential antidepressant medication.

METHODS

The following key phrases were sought in PubMed, Google Scholar, Web of Science, and China National Knowledge Internet (CNKI) without time limitation to search all relevant articles with in vivo or in vitro experimental studies as comprehensively as possible: ('iridoid' or 'seciridoid' or 'depression'). This review extracted the experimental data on the therapeutic potential and molecular mechanism of plant-derived iridoids for depression.

RESULTS

Plant iridoids (i.e., catalpol, geniposide, loganin), and secoiridoids (i.e., morroniside, gentiopicroside, oleuropein, swertiamarin), all showed significant improvement effects on depression.

DISCUSSION AND CONCLUSIONS

Iridoids exert antidepressant effects by elevating monoamine neurotransmitters, reducing pro-inflammatory factors, inhibiting hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, increasing brain-derived neurotrophic factor (BDNF) and its receptors, and elevating intestinal microbial abundance. Further detailed studies on the pharmacokinetics, bioavailability, and key molecular targets of iridoids are also required in future research, ultimately to provide improvements to current antidepressant medications.

Forsythoside B attenuates neuro-inflammation and neuronal apoptosis by inhibition of NF-κB and p38-MAPK signaling pathways through activating Nrf2 post spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is a ruinous neurological pathology that results in locomotor and sensory impairment. Neuro-inflammation and secondary neuronal apoptosis contribute to SCI, with anti-inflammatory therapies the focus of many SCI studies. Forsythoside B (FTS•B), a phenylethanoid glycoside extracted from the leaves of Lamiophlomis rotata Kudo, has been shown previously to have anti-inflammatory properties. Nevertheless, the therapeutic effect of FTS•B on neuro-inflammation after SCI is unknown.

METHODS

Neuro-inflammation was assessed by western blotting (WB), immunofluorescence (IF) staining, and enzyme-linked immunosorbent assay (ELISA) both in vitro and in vivo. Secondary neuronal apoptosis was simulated in a microglia-neuron co-culture model with the degree of apoptosis measured by WB, IF, and TUNEL staining. In vivo, FTS•B (10 mg/kg, 40 mg/kg) were intraperitoneally injected into SCI mice. Morphological changes following SCI were evaluated by Nissl, Hematoxylin-eosin, and Luxol Fast Blue staining. Basso Mouse Scale scores were used to evaluate locomotor function recovery.

RESULTS

FTS•B markedly decreased the levels of iNOS, COX-2 and signature mediators of inflammation. Phosphorylated p38 and nuclear factor-kappa B (NF-κB) were markedly decreased by FTS•B. Additionally, FTS•B-induced inhibition of NF-κB and p38-MAPK signaling pathways was reversed by Nrf2 downregulation. Administration of FTS•B also significantly reduced apoptosis-related protein levels indicating that FTS•B ameliorated secondary neuronal apoptosis. FTS•B administration inhibited glial scar formation, decreased neuronal death, tissue deficiency, alleviated demyelination, and promoted locomotor recovery.

CONCLUSION

FTS•B effectively attenuates neuro-inflammation and secondary neuronal apoptosis by inhibition of NF-κB and p38-MAPK signaling pathways through activating Nrf2 after SCI. This study demonstrates FTS•B to be a potential therapeutic for SCI.

A Comprehensive Review on the Chemical Properties, Plant Sources, Pharmacological Activities, Pharmacokinetic and Toxicological Characteristics of Tetrahydropalmatine

Tetrahydropalmatine (THP), a tetrahydroproberine isoquinoline alkaloid, is widely present in some botanical drugs, such as Stephania epigaea H.S. Lo (Menispermaceae; Radix stephaniae epigaeae), Corydalis yanhusuo (Y.H.Chou & Chun C.Hsu) W.T. Wang ex Z.Y. Su and C.Y. Wu (Papaveraceae; Corydalis rhizoma), and Phellodendron chinense C.K.Schneid (Berberidaceae; Phellodendri chinensis cortex). THP has attracted considerable attention because of its diverse pharmacological activities. In this review, the chemical properties, plant sources, pharmacological activities, pharmacokinetic and toxicological characteristics of THP were systematically summarized for the first time. The results indicated that THP mainly existed in Papaveraceae and Menispermaceae families. Its pharmacological activities include anti-addiction, anti-inflammatory, analgesic, neuroprotective, and antitumor effects. Pharmacokinetic studies showed that THP was inadequately absorbed in the intestine and had rapid clearance and low bioavailability in vivo, as well as self-microemulsifying drug delivery systems, which could increase the absorption level and absorption rate of THP and improve its bioavailability. In addition, THP may have potential cardiac and neurological toxicity, but toxicity studies of THP are limited, especially its long-duration and acute toxicity tests. In summary, THP, as a natural alkaloid, has application prospects and potential development value, which is promising to be a novel drug for the treatment of pain, inflammation, and other related diseases. Further research on its potential target, molecular mechanism, toxicity, and oral utilization should need to be strengthened in the future.

Bio-Active Compounds from Teucrium Plants Used in the Traditional Medicine of Kurdistan Region, Iraq

Herbal medicine is still widely practiced in the Kurdistan Region, Iraq, especially by people living in villages in mountainous regions. Seven taxa belonging to the genus Teucrium (family Lamiaceae) are commonly employed in the Kurdish traditional medicine, especially to treat jaundice, stomachache and abdominal problems. We report, in this paper, a comprehensive account about the chemical structures and bioactivities of most representative specialized metabolites isolated from these plants. These findings indicate that Teucrium plants used in the folk medicine of Iraqi Kurdistan are natural sources of specialized metabolites that are potentially beneficial to human health.