Effects of salidroside on glioma formation and growth inhibition together with improvement of tumor microenvironment

Salidroside alleviates LPS-induced liver injury and inflammation through SIRT1- NF-κB pathway and NLRP3 inflammasome

Objectives

Salidroside (SAL), an active ingredient purified from the medicinal plant Rhodiola rosea, has anti-inflammatory, anti-oxidant, anticancer, and neuroprotective properties. The study aims to examine SAL's protective role in liver damage brought on by lipopolysaccharide (LPS).

Materials and Methods

Six to eight-week-old male C57BL/6 wild-type mice were intraperitoneally treated with 10 mg/kg LPS for 24 hr and 50 mg/kg SAL two hours before LPS administration. Mice were categorized into control, LPS, and LPS + SAL groups. To evaluate liver injury, biochemical and TUNNEL staining test studies were performed. The Elisa assay analyzed interleukin- 1β (IL-1β), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) pro-inflammatory cytokine expression levels. RT-qPCR and western blotting measured mRNA and protein expression of SIRT1, NF-кB, NLRP3, cleaved caspase-1, and GSDMD, respectively.

Results

Analysis of the serum alanine/aspartate aminotransferases (ALT/AST), malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) revealed that SAL protected against hepatotoxicity induced by LPS. The pathological evaluation of the liver supported the protection provided by SAL. SAL treatment reversed IL-1β, TNF-α, and IL-6 pro-inflammatory cytokines after being induced by LPS (all, P<0.001). The western blotting examination results demonstrated that SAL increased the levels of Sirtuin 1 (SIRT1) expression but markedly reduced the phosphorylation of Nuclear Factor Kappa B (NF-B) and the expressions of NLRP3, cleaved caspase-1, and gasdermin D (GSDMD) induced by LPS (all, P<0.001).

Conclusion

Our results speculated that by inhibiting the SIRT1- NF-κB pathway and NLRP3 inflammasome, SAL defends against LPS-induced liver injury and inflammation.

Salidroside attenuates atrial fibrosis and atrial fibrillation vulnerability induced by angiotensin-II through inhibition of LOXL2-TGF-β1-Smad2/3 pathway

Aims and objectives

Salidroside (SAL), an active component isolated from the Chinese plant Rose Rhodiola, has anti-inflammatory, antioxidant, anti-cancer, neuroprotective, and renal protective properties. Atrial fibrosis developed due to angiotensin II (Ang II) plays a crucial function in developing atrial fibrillation (AF). This research investigates the involvement of SAL in AF, its vulnerability to AF, and Ang II-induced inflammatory atrial fibrosis.

Methods

Ang II (2 mg/kg/day) was infused underneath the skin into male C57BL/6 mice (8-10 weeks old, n = 40) for four weeks to create the AF model. SAL (50 mg/kg/day) was given intraperitoneally once per day for 28 days. Analyses of morphology, histology, and biochemical were carried out. Transesophageal burst pacing was used in vivo to induce AF.

Results

Ang II injection increased mice's heart rate and systolic blood pressure (SBP), whereas SAL treatment was significantly reduced. Ang II infusion increased left atrial diameter (LAD) in mice, which was attenuated after SAL treatment. SAL alone did not affect AF inducibility, but SAL therapy markedly decreased Ang II-induced AF inducibility. Additionally, the expression levels of interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were inhibited with SAL therapy in mice. Compared to the Ang II group, Ang II infusion raised malondialdehyde (MDA) levels and reduced superoxide dismutase (SOD) and catalase (CAT) activity, but SAL therapy altered all of these effects. SAL treatment significantly reduced LOXL2, TGF-β1, p-Smad2 and p-Smad3 protein expression than the Ang II group mice.

Conclusion

SAL inhibits atrial fibrosis and potentially attenuates increased susceptibility to AF by suppressing the LOXL2-TGF-β1-Smad2/3 pathway.

Rhodiola rosea polysaccharides promote the proliferation of bone marrow haematopoietic progenitor cells and stromal cells in mice with aplastic anaemia

CONTEXT

The effects of Rhodiola rosea L. (Crassulaceae) polysaccharides (RRPs) on haematopoiesis are poorly understood.

OBJECTIVE

To determine the effects of RRPs on haematopoiesis in mice with aplastic anaemia.

MATERIALS AND METHODS

Aplastic anaemia was induced in Kunming mice by ⁶⁰Coγ (2.0 Gy) irradiation and cyclophosphamide administration (50 mg/kg/day for 3 consecutive days; intraperitoneal injection). The in vivo effects of RRPs (10, 20, and 40 mg/kg; intraperitoneal injection) on haematopoiesis were analyzed using peripheral blood tests, histopathological examination of haematopoietic tissues, culture of haematopoietic progenitors and bone marrow stromal cells (BMSCs), and Western blotting of Fas and Fas ligand (FasL). The in vitro effects of RRPs on bone-marrow haematopoietic progenitors and BMSCs were also evaluated.

RESULTS

Compared to anaemic controls, high-dose RRPs (40 mg/kg) significantly increased red blood cells (8.21 ± 0.57835 versus 6.13 ± 1.34623 × 10¹²/L), white blood cells (5.11 ± 1.6141 versus l.54 ± 1.1539 × 10⁹/L), and BMSCs (10.33 ± 1.5542 versus 5.87 ± 3.1567 × 10¹²/L) in mice with aplastic anaemia (all p < 0.01). High-dose RRPs significantly increased the formation of colony-forming unit-granulocyte macrophage (CFU-GM), burst-forming unit-erythroid (BFU-E), and colony-forming unit-erythroid (CFU-E; p < 0.01). Fas and FasL protein expression in BMSCs decreased after RRPs administration. Especially at the high dose, RRPs (150 μg/mL) significantly promoted in vitro CFUs-E, BFUs-E, and CFUs-GM formation. RRPs (150-300 μg/mL) also promoted BMSC proliferation.

DISCUSSION AND CONCLUSIONS

RRPs helped to promote haematopoietic recovery in mice with aplastic anaemia, facilitating haematopoietic tissue recovery. This study indicated some mechanisms of the haematopoietic regulatory effects of RRPs. Our findings provide a laboratory basis for clinical research on RRPs.

The Promoting Effect of Traumatic Brain Injury on the Incidence and Progression of Glioma: A Review of Clinical and Experimental Research

The role of traumatic brain injury in the development of glioma is highly controversial since first presented. This is not unexpected because traumatic brain injuries are overwhelmingly more common than glioma. However, the causes of post-traumatic glioma have been long discussed and still warrant further research. In this review, we have presented an overview of previous cohort studies and case–control studies. We have summarized the roles of microglial cells, macrophages, astrocytes, and stem cells in post-traumatic glioma formation and development, and reviewed various carcinogenic factors involved during traumatic brain injury, especially those reported in experimental studies indicating a relationship with glioma progression. Besides, traumatic brain injury and glioma share several common pathways, including inflammation and oxidative stress; however, the exact mechanism underlying this co-occurrence is yet to be discovered. In this review, we have summarized current epidemiological studies, clinical reports, pathophysiological research, as well as investigations evaluating the probable causes of co-occurrence and treatment possibilities. More efforts should be directed toward elucidating the relationship between traumatic brain injury and glioma, which could likely lead to promising pharmacological interventions towards designing therapeutic strategies.

Advances and potential pitfalls of oncolytic viruses expressing immunomodulatory transgene therapy for malignant gliomas

Glioblastoma (GBM) is an immunosuppressive, lethal brain tumor. Despite advances in molecular understanding and therapies, the clinical benefits have remained limited, and the life expectancy of patients with GBM has only been extended to ~15 months. Currently, genetically modified oncolytic viruses (OV) that express immunomodulatory transgenes constitute a research hot spot in the field of glioma treatment. An oncolytic virus is designed to selectively target, infect, and replicate in tumor cells while sparing normal tissues. Moreover, many studies have shown therapeutic advantages, and recent clinical trials have demonstrated the safety and efficacy of their usage. However, the therapeutic efficacy of oncolytic viruses alone is limited, while oncolytic viruses expressing immunomodulatory transgenes are more potent inducers of immunity and enhance immune cell-mediated antitumor immune responses in GBM. An increasing number of basic studies on oncolytic viruses encoding immunomodulatory transgene therapy for malignant gliomas have yielded beneficial outcomes. Oncolytic viruses that are armed with immunomodulatory transgenes remain promising as a therapy against malignant gliomas and will undoubtedly provide new insights into possible clinical uses or strategies. In this review, we summarize the research advances related to oncolytic viruses that express immunomodulatory transgenes, as well as potential treatment pitfalls in patients with malignant gliomas.

Protective Evaluation of Compounds Extracted from Root of Rhodiola rosea L. against Methylglyoxal-Induced Toxicity in a Neuronal Cell Line

Rhodiola rosea L. (R. rosea) is one of the most beneficial medicinal plants and it is studied as an adaptogen. This study aims to evaluate the neuroprotective activity of compounds extracted from the root of R. rosea against methylglyoxal (MG)-induced apoptosis in neuro-2A (N2A) cells. The root of R. rosea was extracted with ethanol and partitioned with water, ethyl acetate, and n-butanol fractions to evaluate acetylcholinesterase (AChE) inhibitory activity and neuroprotective activity. The ethyl acetate fraction exhibited the highest values of AChE inhibitory activity (49.2% ± 3%) and cell viability (50.7% ± 4.8%) for neuroprotection. The structure identification of the most potential fraction (ethyl acetate fraction) revealed 15 compounds, consisting of three tannins, five flavonoids, and seven phenolics by infrared spectroscopy, nuclear magnetic resonance, and mass spectroscopy. All compounds were evaluated for their neuroprotective activity. Salidroside had the most potential neuroprotective activity. Gallic acid and methyl gallate had potential cytotoxicity in N2A cells. This study showed that R. rosea might have potential neuroprotective activities.

Advances in Research on Anticancer Properties of Salidroside

Salidroside is a phenolic secondary metabolite present in plants of the genus Rhodiola, and studies investigating its extensive pharmacological activities and mechanisms have recently attracted increasing attention. This review summarizes the progress of recent research on the antiproliferative activities of salidroside and its effects on breast, ovarian, cervical, colorectal, lung, liver, gastric, bladder, renal, and skin cancer as well as gliomas and fibrosarcomas. Thus, it provides a reference for the further development and utilization of salidroside.

The interrelationship between cerebral ischemic stroke and glioma: a comprehensive study of recent reports

Glioma and cerebral ischemic stroke are two major events that lead to patient death worldwide. Although these conditions have different physiological incidences, ~10% of ischemic stroke patients develop cerebral cancer, especially glioma, in the postischemic stages. Additionally, the high proliferation, venous thrombosis and hypercoagulability of the glioma mass increase the significant risk of thromboembolism, including ischemic stroke. Surprisingly, these events share several common pathways, viz. hypoxia, cerebral inflammation, angiogenesis, etc., but the proper mechanism behind this co-occurrence has yet to be discovered. The hypercoagulability and presence of the D-dimer level in stroke are different in cancer patients than in the noncancerous population. Other factors such as atherosclerosis and coagulopathy involved in the pathogenesis of stroke are partially responsible for cancer, and the reverse is also partially true. Based on clinical and neurosurgical experience, the neuronal structures and functions in the brain and spine are observed to change after a progressive attack of ischemia that leads to hypoxia and atrophy. The major population of cancer cells cannot survive in an adverse ischemic environment that excludes cancer stem cells (CSCs). Cancer cells in stroke patients have already metastasized, but early-stage cancer patients also suffer stroke for multiple reasons. Therefore, stroke is an early manifestation of cancer. Stroke and cancer share many factors that result in an increased risk of stroke in cancer patients, and vice-versa. The intricate mechanisms for stroke with and without cancer are different. This review summarizes the current clinical reports, pathophysiology, probable causes of co-occurrence, prognoses, and treatment possibilities.

Cryptotanshinone inhibits lung cancer invasion via microRNA-133a/matrix metalloproteinase 14 regulation

Cryptotanshinone inhibits the proliferative and colony formation abilities of human non-small cell lung cancer cells (NSCLCs). The present study reported that signal transducer and activator of transcription 3 is not the only target of cryptotanshinone during the inhibition of human NSCLCs. It was identified that cryptotanshinone upregulates the expression levels of microRNA (miR)-30d-5p, miR-126-3p, miR-133a, miR-338-3p and miR-451a, and downregulates miR-21-5p, miR-96-5p, miR-182-5p and miR-205-5p. Among these, miR-133a was the most significantly upregulated. miR-133a targets and downregulates the expression of matrix metalloproteinase (MMP)14; however, MMP15, MMP16 and MMP24 were determined to be unaffected. This process was identified to be independent of tissue inhibitor of metalloproteinases 2. Cryptotanshinone also suppresses the invasion of human NSCLCs, which may be due to the inhibited expression of MMP14. In conclusion, cryptotanshinone may serve as a potential therapeutic agent in the treatment of lung cancer.

Natural products: a hope for glioblastoma patients

Glioblastoma (GBM) is one of the most aggressive malignant tumors with an overall dismal survival averaging one year despite multimodality therapeutic interventions including surgery, radiotherapy and concomitant and adjuvant chemotherapy. Few drugs are FDA approved for GBM, and the addition of temozolomide (TMZ) to standard therapy increases the median survival by only 2.5 months. Targeted therapy appeared promising in in vitro monolayer cultures, but disappointed in preclinical and clinical trials, partly due to the poor penetration of drugs through the blood brain barrier (BBB). Cancer stem cells (CSCs) have intrinsic resistance to initial chemoradiation therapy (CRT) and acquire further resistance via deregulation of many signaling pathways. Due to the failure of classical chemotherapies and targeted drugs, research efforts focusing on the use of less toxic agents have increased. Interestingly, multiple natural compounds have shown antitumor and apoptotic effects in TMZ resistant and p53 mutant GBM cell lines and also displayed synergistic effects with TMZ. In this review, we have summarized the current literature on natural products or product analogs used to modulate the BBB permeability, induce cell death, eradicate CSCs and sensitize GBM to CRT.

Rhodiola rosea L.: an herb with anti-stress, anti-aging, and immunostimulating properties for cancer chemoprevention

Purpose of review

Rhodiola rosea extracts have been used as a dietary supplement in healthy populations, including athletes, to non-specifically enhance the natural resistance of the body to both physical and behavior stresses for fighting fatigue and depression. We summarize the information with respect to the new pharmacological activities of Rhodiola rosea extracts and its underlying molecular mechanisms in this review article.

Recent findings

In addition to its multiplex stress-protective activity, Rhodiola rosea extracts have recently demonstrated its anti-aging, anti-inflammation, immunostimulating, DNA repair and anti-cancer effects in different model systems. Molecular mechanisms of Rhodiola rosea extracts's action have been studied mainly along with one of its bioactive compounds, salidroside. Both Rhodiola rosea extracts and salidroside have contrast molecular mechanisms on cancer and normal physiological functions. For cancer, Rhodiola rosea extracts and salidroside inhibit the mTOR pathway and reduce angiogenesis through down-regulation of the expression of HIF-1α/HIF-2α. For normal physiological functions, Rhodiola rosea extracts and salidroside activate the mTOR pathway, stimulate paracrine function and promote neovascularization by inhibiting PHD3 and stabilizing HIF-1α proteins in skeletal muscles. In contrast to many natural compounds, salidroside is water-soluble and highly bioavailable via oral administration and concentrated in urine by kidney excretion.

Summary

Rhodiola rosea extracts and salidroside can impose cellular and systemic benefits similar to the effect of positive lifestyle interventions to normal physiological functions and for anti-cancer. The unique pharmacological properties of Rhodiola rosea extracts or salidroside deserve further investigation for cancer chemoprevention, in particular for human urinary bladder cancer.

When Anti-Aging Studies Meet Cancer Chemoprevention: Can Anti-Aging Agent Kill Two Birds with One Blow?

Recent evidence has strongly supported that the rate of aging is controlled, at least to some extent, by evolutionarily conserved nutrient sensing pathways (e.g. the insulin/IGF-1-signaling, mTOR, AMPK, and sirtuins) from worms to humans. These pathways are also commonly involved in carcinogenesis and cancer metabolism. Agents (e.g. metformin, resveratrol, and Rhodiola) that target these nutrient sensing pathways often have both anti-aging and anti-cancer efficacy. These agents not only reprogram energy metabolism of malignant cells, but also target normal postmitotic cells by suppressing their conversion into senescent cells, which confers systematic metabolism benefits. These agents are fundamentally different from chemotherapy (e.g. paclitaxel and doxorubicin) or radiation therapy that causes molecular damage (e.g. DNA and protein damages) and thereby no selection resistance may be expected. By reviewing molecular mechanisms of action, epidemiological evidence, experimental data in tumor models, and early clinical study results, this review provides information supporting the promising use of agents with both anti-aging and anti-cancer efficacy for cancer chemoprevention.

Bisdemethoxycurcumin attenuates gastric adenocarcinoma growth by inducing mitochondrial dysfunction

Bisdemethoxycurcumin (BDMC) is a demethoxy derivative of curcumin. In this study, a human gastric adenocarcinoma xenograft model was generated in vivo using nude mice and BDMC was observed to suppress the growth and activity of tumors, in addition to improving the physical and mental capacity of the mice. An increased number of apoptotic cells, decreased ratio of B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein and increased caspase-3 expression was also observed following treatment with BDMC, indicating that BDMC may promote apoptosis in tumors via mitochondrial modulation. The growth of SGC 7901 gastric cancer cells was inhibited and arrested at G₁ phase. Specific indicators of mitochondrial dysfunction, a reduction in adenosine triphosphate generation, the inner mitochondrial membrane potential, augmentation of reactive oxygen species production and cytochrome c were also detected in the mitochondria following treatment with BDMC. These results indicate that BDMC attenuates gastric adenocarcinoma growth by inducing mitochondrial dysfunction.

BCNU/PLGA microspheres: a promising strategy for the treatment of gliomas in mice

OBJECTIVE

To investigate the effects of BCNU/PLGA microspheres on tumor growth, apoptosis and chemotherapy resistance in a C57BL/6 mice orthotopic brain glioma model using GL261 cell line.

METHODS

BCNU/PLGA sustained-release microspheres were prepared by the water-in-oil-in-water emulsion technique. GL261 cells were intracranially injected into C57BL/6 mouse by using the stereotactic technology. A total of 60 tumor-bearing mice were randomly and equally divided into three groups: untreated control, PLGA treated, BCNU/PLGA treated. Magnetic resonance imaging (MRI) was taken to evaluate tumor volume. BCNU/PLGA sustained-release wafers were implanted in the treatment group two weeks after inoculation. Survival time and quality were observed. Specimens were harvested, and immunohistochemical staining was used to check the expression of Bax, Bcl-2, and O(6)-methylguanine-DNA methyltransferase (MGMT). Statistical methods was used for analysis of relevant data.

RESULTS

BCNU/PLGA sustained-release wafers were fabricated and implanted successfully. There is statistical difference of survival time between the BCNU/PLGA treated group and control groups (P<0.05). MRI scan showed inhibitory effect of BCNU/PLGA on tumor growth. Compared to the group A and B, BCNU/PLGA decreased the expression of apoptosis related gene Bcl-2 (P<0.05), but did not elevate the expression level of Bax (P>0.05), with the ratio of Bax/Bcl-2 increased. For MGMT protein expression, no statistically significant change was found in treated group (P>0.05).

CONCLUSIONS

Local implantation of BCNU/PLGA microspheres improved the survival quality and time of GL261 glioma-bearing mice significantly, inhibited the tumor proliferation, induced more cell apoptosis, and did not increase the chemotherapy resistance.