Tetrandrine potentiates the glucocorticoid pharmacodynamics via inhibiting P-glycoprotein and mitogen-activated protein kinase in mitogen-activated human peripheral blood mononuclear cells

Cepharanthine synergistically promotes methylprednisolone pharmacodynamics against human peripheral blood mononuclear cells possibly via regulation of P-glycoprotein/glucocorticoid receptor translocation

BACKGROUND

Cepharanthin® alone or in combination with glucocorticoid (GC) has been used to treat chronic immune thrombocytopenia (ITP) since the 1990s. Cepharanthine (CEP) is one of the main active components of Cepharanthin®. The purpose of this study was to investigate the effects of CEP on GC pharmacodynamics on immune cells and analyse the possible action mechanism of their interactions.

METHODS

Peripheral blood mononuclear cells (PBMCs), T lymphocytic leukemia MOLT-4 cells and daunorubicin resistant MOLT-4 cells (MOLT-4/DNR) were used to evaluate the pharmacodynamics and molecular mechanisms. Drug pharmacodynamics was evaluated by WST-8 assay. P-glycoprotein function was examined by rhodamine 123 assay. CD4+CD25+Foxp3+ regulatory T cells and Th1/Th2/Th17 cytokines were detected by flow cytometry. P-glycoprotein expression and GC receptor translocation were examined by Western blot.

RESULTS

CEP synergistically increased methylprednisolone (MP) efficacy with the suppressive effect on the cell viability of PBMCs. 0.3 and 1 μM of CEP significantly inhibited P-glycoprotein efflux function of CD4+ cells, CD8+ cells, and lymphocytes (P<0.05). 0.03~3 μM of CEP also inhibited the P-glycoprotein efflux function in MOLT-4/DNR cells in a concentration-dependent manner (P<0.001). However, 0.03~3 μM of CEP did not influence P-glycoprotein expression. 0.03~0.3 μM of CEP significantly increased the GC receptor distribution from the cytoplasm to the nucleus in a concentration-dependent manner in MOLT-4/DNR cells. The combination did not influence the frequency of CD4+, CD4+CD25+ and CD4+CD25+Foxp3+ T cells or the secretion of Th1/Th2/Th17 cytokines from PBMCs. In contrast, CEP alone at 1 μM decreased the percentage of CD4+ T cell significantly (P<0.01). It also inhibited the secretion of IL-6, IL-10, IL-17, TNF-α, and IFN-γ.

CONCLUSIONS

CEP synergistically promoted MP pharmacodynamics to decrease the cell viability of the mitogen-activated PBMCs, possibly via inhibiting P-glycoprotein function and potentiating GC receptor translocation. The present study provides new evidence of the therapeutic effect of Cepharanthin® alone or in combination with GC for the management of chronic ITP.

Tetrandrine for Targeting Therapy Resistance in Cancer

During the last five decades, there has been tremendous development in our understanding of cancer biology and the development of new and novel therapeutics to target cancer. However, despite these advances, cancer remains the second leading cause of death across the globe. Most cancer deaths are attributed to the development of resistance to current therapies. There is an urgent and unmet need to address cancer therapy resistance. Tetrandrine, a bis-benzyl iso-quinoline, has shown a promising role as an anti-cancer agent. Recent work from our laboratory and others suggests that tetrandrine and its derivatives could be an excellent adjuvant to the current arsenal of anti-cancer drugs. Herein, we provide an overview of resistance mechanisms to current therapeutics and review the existing literature on the anti-cancer effects of tetrandrine and its potential use for overcoming therapy resistance in cancer.

P-Glycoprotein Exacerbates Brain Injury Following Experimental Cerebral Ischemia by Promoting Proinflammatory Microglia Activation

Microglia are activated following cerebral ischemic insult. P-glycoprotein (P-gp) is an efflux transporter on microvascular endothelial cells and upregulated after cerebral ischemia. This study evaluated the effects and possible mechanisms of P-gp on microglial polarization/activation in mice after ischemic stroke. P-gp-specific siRNA and adeno-associated virus (p-AAV) were used to silence and overexpress P-gp, respectively. Middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) were performed in mice and cerebral microvascular endothelial cells (bEnd.3) in vitro, respectively. OGD/R-injured bEnd.3 cells were cocultured with mouse microglial cells (BV2) in Transwell. Influences on acute ischemic stroke outcome, the expression of inflammatory cytokines, and chemokines and chemokines receptors, microglial polarization, glucocorticoid receptor (GR) nuclear translocation, and GR-mediated mRNA decay (GMD) activation were evaluated via reverse transcription real-time polymerase chain reaction, western blot, or immunofluorescence. Silencing P-gp markedly alleviated experimental ischemia injury as indicated by reduced cerebral infarct size, improved neurological deficits, and reduced the expression of interleukin-6 (IL-6) and IL-12 expression. Silencing P-gp also mitigated proinflammatory microglial polarization and the expression of C-C motif chemokine ligand 2 (CCL2) and its receptor CCR2 expression, whereas promoted anti-inflammatory microglia polarization. Additionally, P-gp silencing promoted GR nuclear translocation and the expression of GMD relative proteins in endothelial cells. Conversely, overexpressing P-gp via p-AAV transfection offset all these effects. Furthermore, silencing endothelial GR counteracted all effects mediated by silencing or overexpressing P-gp. Elevated P-gp expression aggravated inflammatory response and brain damage after ischemic stroke by augmenting proinflammatory microglial polarization in association with increased endothelial CCL2 release due to GMD inhibition by P-gp.

Tetrandrine inhibits the proliferation of mesangial cells induced by enzymatically deglycosylated human IgA1 via IgA receptor/MAPK/NF-κB signaling pathway

Objective: Despite the use of renin-angiotensin system blockade and immunosuppressive drugs, including corticosteroids, the current treatment regimens for Immunoglobulins A nephropathy (IgAN) are severely limited. The proliferation of mesangial cell and deposition of deglycosylated human IgA1 immune complex are the most common pathologic features of IgAN. We examined the tetrandrine potential of suppressing the proliferation of mesangial cells and explored its underlying mechanisms with a focus on IgA receptor/MAPK/NF-κB signaling pathway. Methods: Standard human IgA (native IgA) were enzymatically desialylated (deS IgA) or further degalactosylated (deS/deGal IgA) using neuraminidase and β-galactosidase. Rat glomerular mesangial cells (HBZY-1) and human renal mesangial cells (HRMC) stimulated by IgA were used to observe the suppressive effect of tetrandrine. The MTT assay was used to detect the cell viability. The protein expression of IgA receptor/MAPK/NF-κB signaling pathway was examined by Western blot. Cell cycle analysis was measured by flow cytometer. Results: Native IgA and deS IgA showed limited stimulation effect on both HBZY-1 cells and HRMCs, whereas deS/deGal IgA significantly stimulated the proliferation of both HBZY-1 cells and HRMCs (p < 0.05). Compared with non-stimulation of deS/deGal IgA, 1-3 μM of tetrandrine had stronger inhibitory effect on the proliferation of HBZY-1 cells and HRMCs with the stimulation of deS/deGal IgA (p < 0.05), suggesting that tetrandrine possibly inhibited the proliferation of mesangial cells induced by deglycosylated human IgA1 specifically. Molecular mechanism study revealed that tetrandrine decreased the expression of IgA1 receptor, CD71 and β4GALT1, and inhibited the activation of MAPK/NF-κB significantly (p < 0.05). Moreover, these inhibitory effect of tetrandrine caused cell cycle arrest and stopped the cell growth in the S phase companied with the upregulating of cyclin A2 and downregulating of cyclin D1. Conclusion: Taken together, tetrandrine inhibited the proliferation of mesangial cells induced by enzymatically deglycosylated human IgA1 via IgA receptor/MAPK/NF-κB signaling pathway. Based on these potential molecular mechanisms, tetrandrine would be an appealing therapeutic option for IgAN.

Pharmacological Effects and Clinical Prospects of Cepharanthine

Cepharanthine is an active ingredient separated and extracted from Stephania cepharantha Hayata, a Menispermaceae plant. As a bisbenzylisoquinoline alkaloid, cepharanthine has various pharmacological properties, including antioxidant, anti-inflammatory, immunomodulatory, antitumoral, and antiviral effects. Following the emergence of coronavirus disease 2019 (COVID-19), cepharanthine has been found to have excellent anti-COVID-19 activity. In this review, the important physicochemical properties and pharmacological effects of cepharanthine, particularly the antiviral effect, are systematically described. Additionally, the molecular mechanisms and novel dosage formulations for the efficient, safe, and convenient delivery of cepharanthine are summarized.

Enhanced alveo pulmonary deposition of nebulized ciclesonide for attenuating airways inflammations: a strategy to overcome metered dose inhaler drawbacks

Ciclesonide (CIC), an inhaled corticosteroid for bronchial asthma is currently available as metered dose inhaler (CIC–MDI) which possesses a major challenge in the management of the elderly, critically ill patients and children. In this work, nebulized CIC nano-structure lipid particles (CIC-NLPs) were prepared and evaluated for their deep pulmonary delivery and cytotoxicity to provide additional clinical benefits to patients in controlled manner and lower dose. The bio-efficacy following nebulization in ovalbumin (OVA) induced asthma Balb/c mice compared to commercial (CIC–MDI) was also assessed. The developed NLPs of 222.6 nm successfully entrapped CIC (entrapment efficiency 93.3%) and exhibited favorable aerosolization efficiency (mass median aerodynamic diameter (MMAD) 2.03 μm and fine particle fraction (FPF) of 84.51%) at lower impactor stages indicating deep lung deposition without imparting any cytotoxic effect up to a concentration of 100 μg/ml. The nebulization of 40 µg dose of the developed CIC-NLPs revealed significant therapeutic impact in the mitigation of the allergic airways inflammations when compared to 80 µg dose of the commercial CIC–MDI inhaler (Alvesco^®). Superior anti-inflammatory and antioxidative stress effects characterized by significant decrease (p< .0001) in inflammatory cytokines IL-4 and 13, serum IgE levels, malondialdehyde (MDA), nitric oxide (NO), TNF-α, and activated nuclear factor-κB (NF-κB) activity were obvious with concomitant increase in superoxide dismutase (SOD) activity. Histological examination with inhibition of inflammatory cell infiltration in the respiratory tract was correlated well with observed biochemical improvement.

Effects of vitamin K2 combined with methotrexate against mitogen-activated peripheral blood mononuclear cells of healthy subjects and rheumatoid arthritis patients

BACKGROUND

Methotrexate (MTX) is used as anchor drug for patients with early and established rheumatoid arthritis (RA). Vitamin K₂ administration was also reported to be associated with decreased disease activity in RA.

OBJECTIVES

Immunosuppressive pharmacodynamics of vitamin K₂ combined with MTX was investigated.

METHODS

Mitogen-activated peripheral blood mononuclear cells (PBMCs) were used to evaluate immunosuppressive pharmacodynamics of drugs in vitro.

RESULTS

Vitamin K₂ alone dose-dependently suppressed T cell mitogen-activated proliferation of PBMCs of both healthy subjects and RA patients. 446.5 and 2232.5 ng/mL vitamin K₂ significantly decreased the IC₅₀ values of MTX on the proliferation of PBMCs of RA patients, with little influences on the pharmacodynamics of MTX in the healthy PBMCs. 4465 ng/mL vitamin K₂ potentiated the pharmacodynamics of MTX in both RA patients and healthy PBMCs. The additional effects of vitamin K₂ to potentiate the suppressive effects of MTX seemed not to be related to the regulation of CD4⁺ CD25⁺ T cells or CD4⁺ CD25⁺ Foxp3⁺ Treg cells. MTX alone at 100 ng/mL significantly decreased the percentage of CD4⁺ T cells in PBMCs of healthy subjects (p < 0.001) with a slight influence in that of RA patients (not significant) and the combination did not show synergistic inhibitory effect. Vitamin K₂ alone tended to suppress the secretion of IL-17, IFN-γ, and TNF-α from the activated PBMCs of RA patients with smaller influences on the cytokine productions from healthy PBMCs. These additional effects of vitamin K₂ were also observed in combination with MTX.

CONCLUSION

The above information may partially elucidate the potentiation effects of vitamin K₂ on the immunosuppressive efficacy of MTX.

Absolute configuration of tetrandrine and isotetrandrine influences their anti-proliferation effects in human T cells via different regulation of NF-κB

Natural compound tetrandrine was reported to inhibit the proliferation of T cells by inhibiting activation of NF-κB. Chemically, isotetrandrine differs from tetrandrine only in the stereochemistry at the chiral centers. The present study aimed to compare their anti-proliferation effects on human T cells with a focus on NF-κB. The IC₅₀ values of tetrandrine against MOLT-4 cells, MOLT-4/DNR cells, and concanavalin A-activated peripheral blood mononuclear cells of healthy subjects and dialysis patients were 4.43 ± 0.22, 3.62 ± 0.22, 1.91 ± 0.22 and 3.03 ± 0.28 μM, respectively. Whereas, the IC₅₀ values of isotetrandrine against the above immune cells were 2.19 ± 0.27, 2.28 ± 0.33, 1.29 ± 0.14 and 1.55 ± 0.26 μM, respectively. The inhibitory effect of isotetrandrine against the proliferation of T cells was stronger than that of tetrandrine significantly (p < 0.05). Molecular mechanism investigation showed that 10 μM of isotetrandrine largely decreased the expression of p-NF-κB and NF-κB in both MOLT-4 and MOLT-4/DNR T cells (p < 0.05), whereas 10 μM of tetrandrine slightly inhibited the phosphorylation of p-NF-κB with little influence on the expression of NF-κB. Taken together, absolute configurations of tetrandrine and isotetrandrine are suggested to influence on their anti-proliferation effects in human T cells via different regulation of NF-κB.

Effects of sinomenine on the proliferation, cytokine production, and regulatory T-cell frequency in peripheral blood mononuclear cells of rheumatoid arthritis patients

Sinomenine (SN) is a plant-derived alkaloid isolated from Caulis Sinomenii. It has been approved by the State Food and Drug Administration of China for treating rheumatoid arthritis (RA) nearly 20 years ago. To investigate the anti-RA mechanism of SN, a lot of scholars reported the immunosuppressive effect of SN on T lymphocytes. We continued to evaluate the suppressive function of SN by using human peripheral blood mononuclear cells (PBMCs) isolated from RA patients. As the positive control, 10 ng/ml of methylprednisolone (MP) showed the antiproliferation effect on mitogen-activated PBMCs of RA patients significantly (*p < .05). Meanwhile, MP decreased the frequency of CD4⁺ CD25⁺ T cells and suppressed the secretion of inflammatory Th1/Th2/Th17 cytokines such as IL-4, IL-6, IL-10, IL-17, IFN-γ, and TNF-α. However, SN at concentrations of 0.3-30 μM, showed little suppressive effects on the proliferation of PBMCs of RA patients. We did not observe any suppressive effects of SN on percentages of CD4⁺ T cells and CD4⁺ CD25⁺ T cells in the mitogen-activated PBMCs of RA patients. The influence of SN on the percentage of CD4⁺ CD25⁺ Foxp3⁺ T cells was also limited. Finally, even 30 μM of SN did not influence the secretion of Th1/Th2/Th17 cytokine significantly. The present study provided evidence that anti-RA mechanism of SN seems not to be related with the suppressive effects on peripheral T cells.

Molecular mechanisms and therapeutic implications of tetrandrine and cepharanthine in T cell acute lymphoblastic leukemia and autoimmune diseases

Inappropriately activated T cells mediate autoimmune diseases and T cell acute lymphoblastic leukemia (T-ALL). Glucocorticoid and chemotherapeutic agents have largely extended lives of these patients. However, serious side effects and drug resistance often limit the prognosis of considerable number of the patients. The efficient treatment of autoimmune diseases or T-ALL with drug resistance remains an important unmet demand clinically. Bisbenzylisoquinoline alkaloids tetrandrine and cepharanthine have been applied for the treatment of certain types of autoimmune diseases and cancers, while studies on their action mechanisms and their further applications combined with glucocorticoids or chemotherapeutic agents remains to be expanded. This review introduced molecular mechanisms of tetrandrine and cepharanthine in T cells, including their therapeutic implications. Both tetrandrine and cepharnthine influence the growth of activated T cells via several kinds of signaling pathways, such as NF-κB, caspase cascades, cell cycle, MAPK, and PI3K/Akt/mTOR. According to recent preclinical and clinical studies, P-glycoprotein inhibitory effect of tetrandrine and cepharnthine could play a significant role on T cell-involved refractory diseases. Therefore, tetrandrine or cepharanthine combined with glucocorticoid or other anti-leukemia drugs would bring a new hope for patients with glucocorticoid-resistant autoimmune disease or refractory T-ALL accompanied with functional P-glycoprotein. In conclusion, bisbenzylisoquinoline alkaloids tetrandrine and cepharanthine can regulate several signaling pathways in abnormally activated T cells with low toxicity. Bisbenzylisoquinoline alkaloids deserve to be paid more attention as a lead compound to develop new drugs for the treatment of T cell-involved diseases in the future.

Cytotoxic effects of vitamins K1, K2, and K3 against human T lymphoblastoid leukemia cells through apoptosis induction and cell cycle arrest

The present study was undertaken to evaluate cytotoxic effects of vitamin K1 (phylloquinone), vitamin K2 (menaquinones), and vitamin K3 (menadione) against human T lymphoblastoid leukemia cells, Jurkat T cells, MOLT-4 cells, and P-glycoprotein-expressing multidrug-resistant MOLT-4/DNR cells. Vitamins K2 and K3, but not vitamin K1, reduced viabilities of Jurkat, MOLT-4, and MOLT-4/DNR cells. The influence potency of vitamin K3 was larger than that of vitamin K2 in all of the three cell lines. MOLT-4/DNR cells seemed to be more sensitive toward the effects of vitamins K2 and K3. The cytotoxicity of vitamins K2 and K3 on these leukemia cells seems to be related to apoptosis induction and cell cycle arrest. Vitamin K2 and K3 treatment induced cleavage of PARP obviously. Moreover, vitamins K2 and K3 specifically down-regulated the expressions of cyclin A2 in all of the three cell lines. However, the effects of vitamins K2 and K3 on the cell cycle profiling in Jurkat, MOLT-4, and MOLT-4/DNR cells varied with the cell type. Vitamins K2 and K3 also decreased the viability of mitogen-activated human peripheral blood mononuclear cells. Our observations suggest that vitamins K2 and K3 have bilateral cytotoxic effects on activated human peripheral lymphocytes and the human leukemic T cells.

Tetrandrine enhances glucocorticoid receptor translocation possibly via inhibition of P-glycoprotein in daunorubicin-resistant human T lymphoblastoid leukemia cells

Glucocorticoids are used as anticancer and immunosuppressive agents, whereas glucocorticoid resistance has been observed in a significant fraction of patients due to overexpression of P-glycoprotein encoded by multi-drug resistance-1 gene. Tetrandrine is a bisbenzylisoquinoline alkaloid isolated from traditional herb Fangji. According to our previous report, tetrandrine potentiated glucocorticoid pharmacodynamics partially via inhibiting P-glycoprotein function. In the present study, we investigated whether glucocorticoid receptor translocation was influenced indirectly by tetrandrine via P-glycoprotein inhibition, using human T lymphoblastoid leukemia MOLT-4 cell line with little P-glycoprotein expression and its multidrug resistant sub-line MOLT-4/DNR exhibiting a large amount of P-glycoprotein. Molecular mechanism investigation suggested that overexpressed P-glycoprotein weakened the glucocorticoid receptor translocation in MOLT-4/DNR cells comparing with the parent MOLT-4 cells. Our data also suggested that tetrandrine enhanced nuclear glucocorticoid receptor translocation in MOLT-4/DNR cells indirectly by dual influences on P-glycoprotein, inhibiting the efflux function and downregulating the protein expression. Therefore, tetrandrine potentiated the cytotoxic effect of methylprednisolone against MOLT-4/DNR cells with less effects on MOLT-4 cells. These effects of tetrandrine were suggested to be beneficial for the treatment of glucocorticoid resistant diseases induced by the overexpression of P-glycoprotein.

Bisbenzylisoquinoline alkaloids and P-glycoprotein function: A structure activity relationship study

Conflicts with the notion that specific substrate interactions were required in the control of reaction path in active transport systems, P-glycoprotein showed extraordinarily low specificity. Therefore, overexpression P-glycoprotein excluded a large number of anticancer agents from cancer cells, and multidrug resistance happened. Several kinds of bisbenzylisoqunoline alkaloids were reported to modulate P-glycoprotein function and reverse drug resistance. In order to provide more information for their structure activity relationship on P-glycoprotein function, the effects of tetrandrine, isotetrandrine, fangchinoline, berbamine, dauricine, cepharanthine and armepavine on the P-glycoprotein function were compared by using daunorubicin-resistant leukemia MOLT-4 cells in the present study. Among them, tetrandrine exhibited the strongest P-glycoprotein inhibitory effect, followed with fangchinoline and cepharanthine, and subsequently with berbamine or isotetrandrine. However, dauricine and armepavine showed little influence on the P-glycoprotein function. These data revealed that the 18-membered ring of the bisbenzylisoquinoline alkaloids maintained the P-glycoprotein inhibitory activity, suggesting that double isoquinoline units connected by two oxygen bridges were indispensable. Moreover, stereo-configuration of bisbenzylisoquinoline 3D structures determined their inhibitory activities, which provided a new viewpoint to recognize the specificity of binding pocket in P-glycoprotein. Our data also indicated that 3D chemical structure was more sensitive than 2D to predict the P-glycoprotein inhibitory-potencies of bisbenzylisoqunoline alkaloids.

Vitamin K2 immunosuppressive effect on pediatric patients with atopic dermatitis

BACKGROUND

Over 20 kinds of steroids, tacrolimus ointments, and cyclosporine capsules are usually recommended for the treatment of atopic dermatitis (AD), depending on the symptoms of patients. However, several side effects sometimes occur with the extensive use of these agents for the treatment of pediatric AD patients. The purpose of this study was to explore whether vitamin K₂ could be a new immunosuppressive candidate for pediatric patients with AD.

METHODS

The immunosuppressive efficacy of vitamin K₂ was evaluated through a cell-culture procedure using mitogen-activated peripheral blood mononuclear cells (PBMCs) obtained from pediatric AD patients.

RESULTS

The mean (SD) IC₅₀ value of vitamin K₂ for the proliferation of concanavalin A-activated PBMCs was 15.37 (30.05) μmol/L, while the value for tacrolimus was 0.10 (0.28) ng/mL (0.12 (0.35) nmol/L). There was a significant correlation between the IC₅₀ values for vitamin K₂ and those for tacrolimus (P = 0.0001, r = 0.8871). However, there was no significant correlation between the IC₅₀ values of vitamin K₂ and those of cyclosporine A or methylprednisolone. A significant correlation between the IC₅₀ values of vitamin K₂ or tacrolimus and blood eosinophil counts (P = 0.0099, r = 0.7086 and P = 0.0032, r = 0.7722, respectively) was observed.

CONCLUSION

Vitamin K₂ -inhibited T-cell mitogen stimulated proliferation of PBMCs from pediatric AD patients in a dose-dependent manner. The PBMCs from pediatric AD patients were more sensitive to the immunosuppressive efficacy of vitamin K₂ than the PBMCs from healthy subjects. The individual immunosuppressive pharmacological efficacy of vitamin K₂ and of tacrolimus could be inferred from the blood eosinophil count of pediatric AD patients.

Tetrandrine and cepharanthine induce apoptosis through caspase cascade regulation, cell cycle arrest, MAPK activation and PI3K/Akt/mTOR signal modification in glucocorticoid resistant human leukemia Jurkat T cells

Tetrandrine (TET) and cepharanthine (CEP) are two bisbenzylisoquinoline alkaloids isolated from the traditional herbs. Recent molecular investigations firmly supported that TET or CEP would be a potential candidate for cancer chemotherapy. Prognosis of patients with glucocorticoid resistant T cell acute lymphoblastic leukemia (T-ALL) remains poor; here we examined the anti-T-ALL effects of TET and CEP and the underlying mechanism by using the glucocorticoid resistant human leukemia Jurkat T cell line in vitro. TET and CEP significantly inhibited cell viabilities and induced apoptosis in dose- and time-dependent manner. Further investigations showed that TET or CEP not only upregulated the expression of initiator caspases such as caspase-8 and 9, but also increased the expression of effector caspases such as caspase-3 and 6. As the important markers of apoptosis, p53 and Bax were both upregulated by the treatment of TET and CEP. However, TET and CEP paradoxically increased the expression of anti-apoptotic proteins such as Bcl-2 and Mcl-1, and activated the survival protein NF-κB, leading to high expression of p-NF-κB. Cell cycle arrest at S phase accompanied by increase in the amounts of cyclin A2 and cyclin B1, and decrease in cylcin D1 amount in cells treated with TET or CEP will be another possible mechanism. During the process of apoptosis in Jurkat T cells, treatment with TET or CEP also increased the phosphorylation of JNK and p38. The PI3K/Akt/mTOR signaling pathway modification appears to play significant role in the Jurkat T cell apoptosis induced by TET or CEP. Moreover, TET and CEP seemed to downregulate the expressions of p-PI3K and mTOR in an independent way from Akt, since these two drugs strongly stimulated the p-Akt expression. These results provide fundamental insights into the clinical application of TET or CEP for the treatment of patients with relapsed T-ALL.

The effects of vitamin K1 and vitamin K2 on the proliferation, cytokine production and regulatory T-cell frequency in peripheral blood mononuclear cells of paediatric atopic dermatitis patients

We estimated the pharmacological efficacy of vitamin K₁ (VK₁ ) and VK₂ on the mitogen-activated peripheral blood mononuclear cells (PBMCs) of paediatric atopic dermatitis (AD) patients. VK₂ suppressed the in vitro proliferation of T-cell mitogen-activated PBMCs of AD patients. In contrast, VK₁ had little effect on the PBMC proliferation. The IL-2 production from the activated PBMCs of AD patients significantly increased (P < .05), while the production significantly decreased by 100 μmol L^-1 VK₂ (P < .01). In addition, 100 μmol L^-1 VK₂ reduced the percentage of CD4+ and CD4+CD25+ cells in PBMCs. These results suggest that VK2 can modulate T-cell function in PBMCs of AD patients.

Combination therapy with protein kinase inhibitor H89 and Tetrandrine elicits enhanced synergistic antitumor efficacy

BACKGROUND

Tetrandrine, a bisbenzylisoquinoline alkaloid that was isolated from the medicinal plant Stephania tetrandrine S. Moore, was recently identified as a novel chemotherapy drug. Tetrandrine exhibited a potential antitumor effect on multiple types of cancer. Notably, an enhanced therapeutic efficacy was identified when tetrandrine was combined with a molecularly targeted agent. H89 is a potent inhibitor of protein kinase A and is an isoquinoline sulfonamide.

METHODS

The effects of H89 combined with tetrandrine were investigated in vitro with respect to cell viability, apoptosis and autophagy, and synergy was assessed by calculation of the combination index. The mechanism was examined by western blot, flow cytometry and fluorescence microscopy. This combination was also evaluated in a mouse xenograft model; tumor growth and tumor lysates were analyzed, and a TUNEL assay was performed.

RESULTS

Combined treatment with H89 and tetrandrine exerts a mostly synergistic anti-tumor effect on human cancer cells in vitro and in vivo while sparing normal cells. Mechanistically, the combined therapy significantly induced cancer cell apoptosis and autophagy, which were mediated by ROS regulated PKA and ERK signaling. Moreover, Mcl-1 and c-Myc were shown to play a critical role in H89/tetrandrine combined treatment. Mcl-1 ectopic expression significantly diminished H89/tetrandrine sensitivity and amplified c-Myc sensitized cancer cells in the combined treatment.

CONCLUSION

Our findings demonstrate that the combination of tetrandrine and H89 exhibits an enhanced therapeutic effect and may become a promising therapeutic strategy for cancer patients. They also indicate a significant clinical application of tetrandrine in the treatment of human cancer. Moreover, the combination of H89/tetrandrine provides new selectively targeted therapeutic strategies for patients with c-Myc amplification.

Immunosuppressive efficacy of tetrandrine combined with methylprednisolone against mitogen-activated peripheral blood mononuclear cells of haemodialysis patients

Immunosuppressive therapy for prevention of acute rejection episode occasionally causes serious adverse effects, and thus it is important to develop new therapeutic approach for renal transplant recipients. This study evaluated the immunosuppressive pharmacodynamics of tetrandrine (TET) and/or methylprednisolone (MP) in haemodialysis patients in vitro by using the peripheral blood mononuclear cells (PBMCs) isolated from whole blood of haemodialysis patients. The median (range) of MP IC₅₀ values against the proliferation of patients PBMCs was 7.04 (2.30-500.00) ng/mL. In contrast, the median (range) of MP IC₅₀ values against the proliferation of healthy PBMCs was 4.44 (3.19-5.08) ng/mL. The median (range) of TET IC₅₀ values against the proliferation of patients PBMCs was 1.61 (1.04-4.79) μmol/L. Lower concentrations of TET (0.3-300 nmol/L) were able to decrease the IC₅₀ values of MP and thus potentiate the MP immunosuppressive effect on patient PBMCs. The median (range) of MP IC₅₀ values in combination with 0.3, 3, 30, and 300 nmol/L TET were 0.92 (0.49-8.39), 2.10 (0.45-20.00), 0.35 (0.092-1.05), and 0.14 (0.05-6.78) ng/mL, respectively. TET potentiates the MP immunosuppressive pharmacodynamics and thus, it was possible to use the combination of MP and TET to attenuate MP side effects. There were significant correlations between the IC₅₀ values of TET and stimulation indices (P=0.04, r=.58), the IC₅₀ values of TET and the haemodialysis periods (P=0.04, r=.57), or the IC₅₀ values of MP combined with 0.3 nmol/L TET and C-reactive protein concentrations (P=0.04, r=.64), respectively.

Traditional Chinese Medicine for Refractory Nephrotic Syndrome: Strategies and Promising Treatments

Refractory nephrotic syndrome (RNS) is an immune-related kidney disease with poor clinical outcomes. Standard treatments include corticosteroids as the initial therapy and other immunosuppressants as second-line options. A substantial proportion of patients with RNS are resistant to or dependent on immunosuppressive drugs and often experience unremitting edema and proteinuria, cycles of remission and relapse, and/or serious adverse events due to long-term immunosuppression. Traditional Chinese medicine has a long history of treating complicated kidney diseases and holds great potential for providing effective treatments for RNS. This review describes the Chinese medical theories relating to the pathogenesis of RNS and discusses the strategies and treatment options using Chinese herbal medicine. Available preclinical and clinical evidence strongly supports the integration of traditional Chinese medicine and Western medicine for improving the outcome of RNS. Herbal medicine such as Astragalus membranaceus, Stephania tetrandra S. Moore, and Tripterygium wilfordii Hook F can serve as the alternative therapy when patients fail to respond to immunosuppression or as the complementary therapy to improve therapeutic efficacy and reduce side effects of immunosuppressive agents. Wuzhi capsules (Schisandra sphenanthera extract) with tacrolimus and tetrandrine with corticosteroids are two herb-drug combinations that have shown great promise and warrant further studies.

Design and synthesis of novel C14-urea-tetrandrine derivatives with potent anti-cancer activity

Tetrandrine is a dibenzyltetrahydroisoquinoline alkaloid, isolated from traditional Chinese medicinal plant Stephania tetrandra, with anti-tumor activity. Our previous study identified several derivatives of tetrandrine showing better activities than parental compound against human hepatocellular carcinoma cells. To increase diversity and cytotoxic activities of the original compound, a series of novel 14-urea-tetrandrine derivatives were synthesized through structural modification of tetrandrine. These derivaties demonstrated a moderate to strong anti-proliferative activities against human cell lines HEL and K562 (Leukemia), prostate (PC3), breast (MDA-MB-231) and melanoma (WM9). Compound 4g showed strongest cytotoxic effect against PC3 cells with IC₅₀ value of 0.64 μM, which was 12-fold, 31-fold and 26-fold lower than the parental tetrandrine, 5-fluorouracil and cisplatin, respectively. Preliminary structure-activity relationship study indicated that urea subsititution was the key pharmacophore for the enhancement of their antitumor activities. Induction of apoprosis by 4g was associated with the activation of pro-apoptotic protein BAX and inhibition of antiapoptosis proteins survivin as well as Bcl-2. Moreover, activation of caspases led to increase cleavage of PARP, which further accelerates apoptotic cell death. These results reveal that the compound 4g may be used as a potential anticancer drug candidate.