Study on the Critical Roles of Apoptosis in Asthma Disease

Inflammation, and remodeling in airways are the two crucial characteristics of asthma, a common respiratory disease. In asthma pathophysiology, the recruitment of granulocytes finally results in inflammation, leading to lung damage. In this regard, failure to clear inflammatory cells by programmed cell death, apoptosis will cause the prolongation of inflammation. On the other hand, in airway epithelial cells, apoptosis may occur, resulting in airway remodeling. Hence, dysregulation of apoptosis has been suggested to contribute to the development of asthma. Importantly, knowledge of the factors related to apoptotic cascade seems vital to explore various pharmacological interventions for the treatment of asthma. In this review, we highlight several important apoptotic and anti-apoptotic factors contributing either to inflammatory cells or airway epithelial cells involved in asthma pathogenesis.

Anti-cancer potential of cannabis terpenes in a taxol-resistant model of breast cancer

Chemotherapeutic resistance can limit breast cancer outcomes; therefore, the exploration of novel therapeutic options is warranted. Isolated compounds found in cannabis have previously been shown to exhibit anti-cancer effects, but little is known about their effects in resistant breast cancer. Our study aims to evaluate the effects of terpenes found in cannabis in in vitro chemotherapy-resistant model of breast cancer. We aimed to identify whether five terpenes found in cannabis produced anti-cancer effects, and if their effects were improved upon co-treatment with cannabinoids and flavonoids also found in cannabis. Nerolidol and β-caryophyllene produced the greatest cytotoxic effects, activated the apoptotic cascade and reduced cellular invasion. Combinations with the flavonoid kaempferol potentiated the cytotoxic effects of ocimene, terpinolene, and β-myrcene. Combinations of nerolidol and δ9-tetrahydrocannabinol or cannabidiol produced variable responses ranging from antagonism and additivity to synergy, depending on concentrations used. Our results indicate that cannabis terpenes, alone or combined with cannabinoids and flavonoids, produced anti-cancer effects in chemotherapy-resistant breast cancer cell lines. This study is a first step in the identification of compounds that could have therapeutic potential in the treatment of resistant breast cancer.

A new Mfn-2 related synthetic peptide promotes vascular smooth muscle cell apoptosis via regulating the mitochondrial apoptotic pathway by inhibiting Akt signaling

Background Restenosis after angioplasty is a major challenge for the treatment of coronary artery diseases. Facilitation of vascular smooth muscle cell (VSMC) apoptosis may be an attractive approach to decrease the incidence of restenosis. We synthesized a 16-amino acid mitofusin-2 (Mfn-2) gene related peptide (MRSP) based on the sequence of the p21ras signature motif, the smallest functional sequence of the Mfn-2 gene with proapoptotic properties in VSMC. We investigated whether MRSP enhanced apoptotic activities to inhibit VSMC accumulation and neointimal hyperplasia in rats with carotid balloon injury. Methods VSMCs were treated with different concentrations of MRSP, the PI3K agonist 740 Y-P and the inhibitor LY294002. Cell apoptosis and related pathway molecules were assessed. MRSP was also given to rats with carotid artery balloon injury. Neointimal hyperplasia and cell apoptotic pathways were detected. Results In vitro experiments revealed that MRSP treatment significantly increased VSMC apoptosis and induced increases in procaspase-9 cleavage, caspase-3 activation, cytochrome c release from mitochondria to the cytoplasm and the Bax/Bcl-2 ratio but not caspase-8 expression, indicating that the mitochondrial apoptotic cascade was activated by MRSP, which might be attributed to suppression of the PI3K/Akt signaling pathway. We further found that the PI3K agonist 740 Y-P prevented and that the inhibitor LY294002 strengthened the proapoptotic effects of MRSP. MRSP strongly inhibited neointimal hyperplasia and VSMC accumulation, but increased VSMC apoptosis in the vascular wall after balloon injury. Moreover, MRSP substantially enhanced Bax and cleaved caspase-3 expression and decreased Bcl-2 levels in intima, accompanied by decreased levels of phosphorylated Akt and PI3K in vivo. Conclusions Taken together, the present study showed that MRSP treatment results in a strong proapoptotic effect by activating the mitochondrial apoptotic cascade through suppression of the PI3K/Akt pathway.

Evaluation of the potential role of silver nanoparticles loaded with berberine in improving anti-tumor efficiency

Background: Cancer is a progressive disease, its incidence and death rates are rapidly increasing globally. Numerous adverse effects are associated with the available interventions. Hence, the current study was undertaken to explore the anticancer effect of silver nanoparticles conjugated with berberine (AgNPs-BER) against Ehrlich solid carcinoma (ESC) in mice. Methods: Male Swiss albino mice were allocated randomly into ESC, ESC+cisplatin (CP; 5 mg/kg), ESC+AgNPs-BER (20 mg/kg), and ESC+cisplatin and AgNPs-BER groups. Results: AgNPs-BER administration increased significantly the survival rate and decreased body weight and tumor size as compared to ESC group. Additionally, AgNPs-BER enhanced the development of oxidative stress in the tumor tissue as indicated by the increased lipid peroxidation (LPO) and nitric oxide (NO) accompanied by a decrease in the examined antioxidant proteins (glutathione (GSH) and its derived enzymes along with superoxide dismutase and catalase). AgNPs-BER was found also to trigger apoptotic cascade in the tumor cells through upregulating the mRNA expression of the pro-apoptotic proteins (Bax and caspase-3) and downregulating the mRNA expression of the anti-apoptotic protein (Bcl-2). Moreover, AgNPs-BER improved partially the histopathological alterations in the developed tumor tissue as compared to ESC group. Conclusion: Collectively, AgNPs-BER could be applied as an antitumor agent due to its pro-oxidant, pro-apoptotic, and antiangiogenic effects.

Intermittent Hypobaric Hypoxic Preconditioning Provides Neuroprotection by Increasing Antioxidant Activity, Erythropoietin Expression and Preventing Apoptosis and Astrogliosis in the Brain of Adult Rats Exposed to Acute Severe Hypoxia

Background: Exposure to intermittent hypoxia has been demonstrated to be an efficient tool for hypoxic preconditioning, preventing damage to cells and demonstrating therapeutic benefits. We aimed to evaluate the effects of respiratory intermittent hypobaric hypoxia (IHH) to avoid brain injury caused by exposure to acute severe hypoxia (ASH). Methods: biomarkers of oxidative damage, mitochondrial apoptosis, and transcriptional factors in response to hypoxia were assessed by Western blot and immunohistochemistry in brain tissue. Four groups of rats were used: (1) normoxic (NOR), (2) exposed to ASH (FiO2 7% for 6 h), (3) exposed to IHH for 3 h per day over 8 days at 460 mmHg, and (4) ASH preconditioned after IHH. Results: ASH animals underwent increased oxidative-stress-related parameters, an upregulation in apoptotic proteins and had astrocytes with phenotype forms compatible with severe diffuse reactive astrogliosis. These effects were attenuated and even prevented when the animals were preconditioned with IHH. These changes paralleled the inhibition of NF-κB expression and the increase of erythropoietin (EPO) levels in the brain. Conclusions: IHH exerted neuroprotection against ASH-induced oxidative injury by preventing oxidative stress and inhibiting the apoptotic cascade, which was associated with NF-κB downregulation and EPO upregulation.

Anti-cancer properties of cannabidiol and Δ9-tetrahydrocannabinol and potential synergistic effects with gemcitabine, cisplatin and other cannabinoids in bladder cancer

Introduction: With the legalization of cannabis in multiple jurisdictions throughout the world, a larger proportion of the population consumes cannabis. Several studies have demonstrated anti-tumor effects of components present in cannabis in different models. Unfortunately, little is known about the potential anti-tumoral effects of cannabinoids in bladder cancer, and how cannabinoids could potentially synergize with chemotherapeutic agents. Our study aims to identify whether a combination of cannabinoids, like cannabidiol and Δ9-tetrahydrocannabinol with agents commonly used to treat bladder cancer, such as gemcitabine and cisplatin, is able to produce desirable synergistic effects. We also evaluated whether co-treatment of different cannabinoids also generated synergistic effects. Materials and Methods: We generated concentration curves with different drugs to identify the range at which they could exert anti-tumor effects. We also evaluated the activation of the apoptotic cascade and whether cannabinoids have the ability to reduce invasion. Results: Cannabidiol, Δ9-tetrahydrocannabinol and other cannabinoids reduce cell viability of bladder cancer cell lines, and their combination with gemcitabine or cisplatin may induce differential responses: from antagonistic to additive and synergistic effects, depending on the concentrations used. Cannabidiol and Δ9-tetrahydrocannabinol were also shown to induce caspase 3 cleavage and reduce invasion in a Matrigel assay. Cannabidiol and Δ9-tetrahydrocannabinol also display synergistic properties with other cannabinoids like cannabichromene or cannabivarin. Discussion: Our results indicate that cannabinoids can reduce human bladder transitional cell carcinoma cell viability, and that they can potentially exert synergistic effects when combined with other agents. Our in vitro results will form the basis for future studies in vivo and in clinical trials for the development of new therapies that could be beneficial for the treatment of bladder cancer in the future.

Therapeutic targeting of FOS in mutant TERT cancers through removing TERT suppression of apoptosis via regulating survivin and TRAIL-R2

The telomerase reverse transcriptase (TERT) has long been pursued as a direct therapeutic target in human cancer, which is currently hindered by the lack of effective specific inhibitors of TERT. The FOS/GABPB/(mutant) TERT cascade plays a critical role in the regulation of mutant TERT, in which FOS acts as a transcriptional factor for GABPB to up-regulate the expression of GABPB, which in turn activates mutant but not wild-type TERT promoter, driving TERT-promoted oncogenesis. In the present study, we demonstrated that inhibiting this cascade by targeting FOS using FOS inhibitor T-5224 suppressed mutant TERT cancer cells and tumors by inducing robust cell apoptosis; these did not occur in wild-type TERT cells and tumors. Mechanistically, among 35 apoptotic cascade-related proteins tested, the apoptosis induced in this process specifically involved the transcriptional activation of tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) and inactivation of survivin, two key players in the apoptotic cascade, which normally initiate and suppress the apoptotic cascade, respectively. These findings with suppression of FOS were reproduced by direct knockdown of TERT and prevented by prior knockdown of TRAIL-R2. Further experiments demonstrated that TERT acted as a direct transcriptional factor of survivin, up-regulating its expression. Thus, this study identifies a therapeutic strategy for TERT promoter mutation-driven cancers by targeting FOS in the FOS/GABPB/(mutant) TERT cascade, circumventing the current challenge in pharmacologically directly targeting TERT itself. This study also uncovers a mechanism through which TERT controls cell apoptosis by transcriptionally regulating two key players in the apoptotic cascade.

Bio-Functional Sperm Parameters: Does Age Matter?

The evaluation of biofunctional sperm parameters can explain some cases of idiopathic male infertility. Among these, sperm DNA fragmentation (fDNA) is the most studied biofunctional sperm parameter. Mitochondrial membrane potential (MMP) correlates positively with sperm motility, the evaluation of sperm apoptosis by flow cytometry allows us to identify a population of spermatozoa not recognizable at the optical microscopy and finally, lipid peroxidation (LP) and mitochondrial superoxide levels measurements are rational oxidative stress indices. Male age seems to affect sperm concentration and sperm fDNA. For these reasons, this study was undertaken to evaluate the correlation, if any, between male age and biofunctional sperm parameters evaluating their possible impact on fDNA. To accomplish this, MMP, degree of chromatin compactness, sperm apoptosis/vitality, fDNA, LP, and mitochondrial superoxide levels were evaluated by flow cytometry in a cohort of 874 men. A significant negative correlation was found between age and the percentage of alive spermatozoa (r = -0.75, p < 0.05). The percentage of spermatozoa with low MMP (L-MMP) correlated positively with the percentage of spermatozoa with abnormal chromatin compactness (r = 0.24, p < 0.05). Spermatozoa with abnormal chromatin compactness and L-MMP correlated negatively with the percentage of alive spermatozoa (r = 0.83, p < 0.05) and positively with spermatozoa with PS externalization (r = 0.13, p < 0.01). The percentage of alive spermatozoa correlated negatively with both the percentage of spermatozoa with PS externalization (r = 0.24, p < 0.01) and of the spermatozoa with fDNA (r = 0.10, p < 0.05). Spermatozoa with PS externalization correlated positively with the percentage of spermatozoa with fDNA (r = 0.09, p < 0.05). Spermatozoa with LP correlated positively with the percentage of spermatozoa with increased mitochondrial superoxide (r = 0.11, p < 0.01) In conclusion, these findings in a large number of men suggest that age, mitochondrial damage, and alteration of chromatin compactness could activate the apoptotic cascade which could result in an increased fDNA rate.

Aronia melanocarpa Ameliorates Adrenal Cytoarchitecture Against the Hexavalent Chromium-Induced Injury

Hexavalent chromium is a toxin that penetrates the cell, triggering reactive oxygen species (ROS) production. Aronia melanocarpa, due to its proanthocyanidins, anthocyanins, and phenolic acid contents, is a valuable antioxidant. The aim was to observe the influence of hexavalent chromium Cr(VI) on the adrenal gland, and if this impact can be recovered by the administration of A. melanocarpa. Accordingly, 36 rats were divided into six groups: control; Aronia; Cr receiving Cr(VI) in distilled water for 3 months; CrA receiving a mix of Cr(VI) and A. melanocarpa at 2.5% aqueous extract for 3 months; Cr2 receiving, for 3 months, Cr(VI) in distilled water, and next, for 1 month, only distilled water; and respectively, CrA2 receiving, for 3 months, Cr(VI) in distilled water, followed by 1 month of Aronia at 2.5% extract administration. The adrenal gland samples were examined toward histological and molecular assessment, and results were statistically analyzed (ANOVA). Hexavalent chromium induced changes in the adrenal cortex expressed by focal or diffuse hypertrophies, cytoplasmic vacuolization (due to lipidic accumulation), and cells’ shape and size alteration, including necrosis. These structural alterations were carried by Bax and Bcl2 gene expression: the Bax gene expression levels, increased significantly (p < 0.001) in all experimental groups, except the Aronia group, compared with control. In the Cr2, CrA, and CrA2 groups, notable reduction of Bax gene expression (p < 0.001) was reported compared with the Cr group. Regarding the Bcl2 gene expression (p < 0.001), a significant increase was observed in the experimental groups, compared with the control. The Bcl2 expression level had a similar pattern to Bax gene, consequently trying to compensate its overexpression. Aronia administered concomitantly, or after Cr(VI), diminished structural changes and expression of the studied genes, thus reducing the Bax/Bcl2 ratio and suggesting that the active ingredients from Aronia are capable of blocking apoptotic cascade induced by the pathway of Bax and Bcl2 proteins.

Aspirin Induced Glioma Apoptosis through Noxa Upregulation

Clinically, high cyclooxygenase-2 expression in malignant glioma correlates well with poor prognosis and the use of aspirin is associated with a reduced risk of glioma. To extend the current understanding of the apoptotic potential of aspirin in most cell types, this study provides evidence showing that aspirin induced glioma cell apoptosis and inhibited tumor growth, in vitro and in vivo. We found that the human H4 glioma cell-killing effects of aspirin involved mitochondria-mediated apoptosis accompanied by endoplasmic reticulum (ER) stress, Noxa upregulation, Mcl-1 downregulation, Bax mitochondrial distribution and oligomerization, and caspase 3/caspase 8/caspase 9 activation. Genetic silencing of Noxa or Bax attenuated aspirin-induced viability loss and apoptosis, while silencing Mcl-1 augmented the effects of aspirin. Data from genetic and pharmacological studies revealed that the axis of ER stress comprised an apoptotic cascade leading to Noxa upregulation and apoptosis. The apoptotic programs and mediators triggered by aspirin in H4 cells were duplicated in human U87 glioma cell line as well as in tumor-bearing BALB/c nude mice. The involvement of ER stress in indomethacin-induced Mcl-1 downregulation was reported in our previous study on glioma cells. Therefore, the aforementioned phenomena indicate that ER stress may be a valuable target for intervention in glioma apoptosis.