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1.
Int J Biol Sci ; 18(14): 5489-5502, 2022.
Article in English | MEDLINE | ID: mdl-36147472

ABSTRACT

Diabetic nephropathy (DN) is a major cause of end-stage kidney disease, where TGF-ß1/Smad signaling plays an important role in the disease progression. Our previous studies demonstrated a combination of Traditional Chinese Medicine derived Smad7 agonist Asiatic Acid (AA) and Smad3 inhibitor Naringenin (NG), AANG, effectively suppressed the progression of renal fibrosis in vivo. However, its implication in type-2 diabetic nephropathy (T2DN) is still unexplored. Here, we detected progressive activation of Smad3 but reduction of Smad7 in db/db mice during T2DN development. Therefore, we optimized the dosage and the combination ratio of AANG to achieve a better rebalancing Smad3/Smad7 signaling for treatment of T2DN. Unexpectedly, preventive treatment with combined AANG from week 4 before the development of diabetes and T2DN effectively protected against the onset of T2DN. In contract, these inhibitory effects were lost when db/db mice received the late AANG treatment from 12-24 weeks. Surprisingly, preventive treatment with AANG ameliorated not only T2DN but also the primary disease type-2 diabetes (T2D) with relative normal levels of fasting blood glucose and HbA1c, and largely improving metabolic abnormalities especially on insulin insensitivity and glucose tolerance in db/db mice. Mechanistically, AANG effectively prevented both Smad3-mediated renal fibrosis and NF-κB-driven renal inflammation in the diabetic kidney in vivo and advanced glycation end-products (AGE) stimulated tubular epithelial mTEC cells in vitro. More importantly, we uncovered that preventive treatment with AANG effectively protected against diabetic-associated islet injury via restoring the ß cell development in db/db mice. Taken together, we discovered that the early treatment with combined AANG can effectively protect against the development of T2D and T2DN via mechanism associated with protection against Smad3-depenedent islet injury.


Subject(s)
Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Insulins , Animals , Blood Glucose , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/metabolism , Fibrosis , Glycated Hemoglobin/metabolism , Insulins/metabolism , Mice , NF-kappa B/metabolism , Smad3 Protein/metabolism , Transforming Growth Factor beta1/metabolism
2.
J Cell Mol Med ; 25(20): 9805-9813, 2021 10.
Article in English | MEDLINE | ID: mdl-34514726

ABSTRACT

Cancer cells are high in heterogeneity and versatility, which can easily adapt to the external stresses via both primary and secondary resistance. Targeting of tumour microenvironment (TME) is a new approach and an ideal therapeutic strategy especially for the multidrug resistant cancer. Recently, we invented AANG, a natural compound formula containing traditional Chinese medicine (TCM) derived Smad3 inhibitor Naringenin (NG) and Smad7 activator Asiatic Acid (AA), for rebalancing TGF-ß/Smad signalling in the TME, and its implication on the multidrug resistance is still unexplored. Here, we observed that an equilibrium shift of the Smad signalling in patients with hepatocellular carcinoma (HCC), which was dramatically enhanced in the recurrent cases showing p-glycoprotein overexpression. We optimized the formula ratio and dosage of AANG that effectively inhibit the proliferation of our unique human multidrug resistant subclone R-HepG2. Mechanistically, we found that AANG not only inhibits Smad3 at post-transcriptional level, but also upregulates Smad7 at transcriptional level in a synergistic manner in vitro. More importantly, AANG markedly suppressed the growth and p-glycoprotein expression of R-HepG2 xenografts in vivo. Thus, AANG may represent a novel and safe TCM-derived natural compound formula for overcoming HCC with p-glycoprotein-mediated multidrug resistance.


Subject(s)
Antineoplastic Agents/pharmacology , Biological Products/pharmacology , Drug Resistance, Neoplasm/drug effects , Signal Transduction/drug effects , Smad Proteins/metabolism , Transforming Growth Factor beta/metabolism , Aged , Animals , Carcinoma, Hepatocellular , Cell Line, Tumor , Disease Models, Animal , Drug Synergism , Humans , Immunohistochemistry , Liver Neoplasms/etiology , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Mice , Middle Aged , Xenograft Model Antitumor Assays
3.
Front Public Health ; 9: 706346, 2021.
Article in English | MEDLINE | ID: mdl-35174128

ABSTRACT

Traditional discipline-specific training has limitations in facilitating inter-professional communication and collaboration. To address this issue, two local universities in Hong Kong launched an interprofessional team-based learning program to allow the undergraduate healthcare students to form teams and experience collaborative problem-solving. This study aimed to evaluate the experiences of nursing and physiotherapy undergraduates following interprofessional learning activities. Twenty-seven 3rd-year nursing and physiotherapy undergraduates were recruited through purposive sampling. Semi-structured interviews were conducted, and written feedback was solicited until data saturation was achieved. An inductive thematic analysis was used for the data, and each theme was mutually exclusive. The findings revealed the positive experiences of the students with this interprofessional learning activity. Three main themes emerged: (1) the process of interprofessional learning; (2) profession-related outcomes of interprofessional learning; and (3) patient-related outcomes of interprofessional learning. The study indicated that interprofessional team-based learning activities enhanced learning experiences of the students through interactive learning with other healthcare students. Experiences of relationships that are trustful and complementary allow students to develop confidence in knowledge transfer and in interprofessional collaboration, as well as in providing a holistic patient-centered care. These findings substantiate the importance and value of interprofessional learning in healthcare education.


Subject(s)
Students, Health Occupations , Students, Nursing , Humans , Physical Therapy Modalities , Qualitative Research
4.
Phytomedicine ; 52: 147-156, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30599894

ABSTRACT

BACKGROUND: As an effective antimalarial medicine, Dihydroartemisinin (DHA) has therapeutic potential on human cervical cancer. However, its working mechanism has not been elucidated. PURPOSE: This study aimed to investigate the reversal effect of DHA on human cervical cancer HeLa cells, and explored its mechanism of action in vitro and in vivo. STUDY DESIGN/METHODS: The effect and mechanism of DHA on HeLa cells was examined by using CCK-8 assay, flow cytometry, transmission electron microscopy, immunofluorescence, and Western blot analysis in human hepatocellular carcinoma cells. RESULTS: In this study, it was confirmed that DHA had statistically equivalent anti-tumor efficiency in HeLa cells with a clinical chemotherapeutic agent of cisplatin. Meanwhile, DHA triggered autophagy, where LC3B-II expression was dose-dependently increased. Further, it was revealed that DHA promotes reactive oxygen species (ROS) generation, with DNA double-strand breaks (DSB) damage, as up-regulation of γH2AX protein and foci formation. Interestingly, we firstly demonstrated that DHA induced autophagy through promotion of the phosphorylation of Bcl-2 (Ser70), independent of the phosphorylated JNK1/2 (Thr183/Tyr185). Moreover, DHA-treated HeLa cells displayed an increase in the pro-autophagic protein Beclin-1 with downregulated the phospho-mTOR (Ser2448). Furthermore, upregulated pro-apoptotic protein Bak-1, but not Bax, suggesting Bak-1 is included in DHA-induced autophagy. CONCLUSION: Therefore, DHA upregulates the phosphorylation of Bcl-2 (Ser70) and mTOR (Ser2448) and induces autophagic cell death in Hela cells. This study provided a mechanism to support DHA, an autophagy inducer, as a potential therapeutic agent for human cervical cancer.


Subject(s)
Antimalarials/pharmacology , Antineoplastic Agents/pharmacology , Artemisinins/pharmacology , Autophagy/drug effects , Proto-Oncogene Proteins c-bcl-2/chemistry , Apoptosis , Beclin-1/metabolism , Cisplatin/pharmacology , DNA Breaks, Double-Stranded , Female , HeLa Cells , Humans , Phosphorylation , Reactive Oxygen Species/metabolism , TOR Serine-Threonine Kinases/metabolism , Up-Regulation , Uterine Cervical Neoplasms , bcl-2 Homologous Antagonist-Killer Protein/metabolism
5.
BMC Infect Dis ; 17(1): 604, 2017 09 04.
Article in English | MEDLINE | ID: mdl-28870175

ABSTRACT

BACKGROUND: Every year, over 1 million people develop isoniazid (INH) resistant tuberculosis (TB). Yet, the optimal treatment regimen remains unclear. Given increasing prevalence, the clinical efficacy of regimens used by physicians is of interest. This study aims to examine treatment outcomes of INH resistant TB patients, treated under programmatic conditions in British Columbia, Canada. METHODS: Medical charts were retrospectively reviewed for cases of culture-confirmed INH mono-resistant TB reported to the BC Centre for Disease Control (BCCDC) from 2002 to 2014. Treatment regimens, patient and strain characteristics, and clinical outcomes were analysed. RESULTS: One hundred sixty five cases of INH mono-resistant TB were included in analysis and over 30 different treatment regimens were prescribed. Median treatment duration was 10.5 months (IQR 9-12 months) and treatment was extended beyond 12 months for 26 patients (15.8%). Fifty six patients (22.6%) experienced an adverse event that resulted in a drug regimen modification. Overall, 140 patients (84.8%) had a successful treatment outcome while 12 (7.2%) had an unsuccessful treatment outcome of failure (n = 2; 1.2%), relapse (n = 4; 2.4%) or all cause mortality (n = 6; 3.6%). CONCLUSION: Our treatment outcomes, while consistent with findings reported from other studies in high resource settings, raise concerns about current recommendations for INH resistant TB treatment. Only a small proportion of patients completed the recommended treatment regimens. High quality studies to confirm the effectiveness of standardized regimens are urgently needed, with special consideration given to trials utilizing fluoroquinolones.


Subject(s)
Antitubercular Agents/therapeutic use , Drug Resistance, Bacterial/drug effects , Isoniazid/therapeutic use , Tuberculosis/drug therapy , Adult , British Columbia/epidemiology , Female , Fluoroquinolones/therapeutic use , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Mycobacterium tuberculosis/drug effects , Recurrence , Retrospective Studies , Treatment Outcome , Tuberculosis/epidemiology , Tuberculosis/microbiology
6.
J Ethnopharmacol ; 131(1): 95-103, 2010 Aug 19.
Article in English | MEDLINE | ID: mdl-20558270

ABSTRACT

AIM OF THE STUDY: Scutellaria barbata is a traditional Chinese medicine for cancer treatments. Pheophorbide-a (Pa), one of the active components isolated from this herbal medicine has been proposed to be a potential natural photosensitizer for photodynamic therapy. The anti-tumor effect of pheophorbide-a based photodynamic therapy (Pa-PDT) has been successfully demonstrated in a wide range of human malignant cell lines. However, the effectiveness of Pa-PDT has not yet been evaluated on human breast cancer, which is documented as the second common and the fifth most lethal cancer worldwide. MATERIALS AND METHODS: The cytotoxicity of Pa-PDT was evaluated by using an estrogen receptor (ER)-negative human breast adenocarcinoma cell line MDA-MB-231. The involvement of mitochondria was revealed by the change of mitochondrial membrane potential and the increase of intracellular reactive oxygen species (ROS). The hallmarks of apoptosis, ER stress and autophagy were also assessed by DNA fragmentation, Western blotting, and immunostaining assays. RESULTS: Pa-PDT showed inhibitory effect on the growth of MDA-MB-231 cells with an IC(50) value of 0.5 microM at 24h. Mitogen-activated protein kinase (MAPK) pathway was found to be triggered, where activation of c-Jun N-terminal kinase (JNK) and inhibition of extracellular signal-regulated kinase (ERK) were occurred in the Pa-PDT-treated cells. Our findings suggested that Pa-PDT exhibited its anti-tumor effects by the activation of mitochondria-mediated apoptosis and the ERK-mediated autophagy in MDA-MB-231 cells. CONCLUSION: The present study suggested Pa-PDT is a potential protocol for the late phase human breast cancer, and it is the first study to demonstrate the Pa-PDT induced autophagy contributed to the anti-tumor effects of Pa-PDT on human cancer cells.


Subject(s)
Adenocarcinoma , Breast Neoplasms , Chlorophyll/analogs & derivatives , Extracellular Signal-Regulated MAP Kinases/antagonists & inhibitors , Plant Extracts/pharmacology , Receptors, Estrogen/deficiency , Scutellaria , Adenocarcinoma/drug therapy , Adenocarcinoma/enzymology , Apoptosis/drug effects , Apoptosis/physiology , Autophagy/drug effects , Autophagy/physiology , Breast Neoplasms/drug therapy , Breast Neoplasms/enzymology , Cell Line, Tumor , Chlorophyll/isolation & purification , Chlorophyll/pharmacology , Chlorophyll/therapeutic use , Extracellular Signal-Regulated MAP Kinases/physiology , Female , Humans , Plant Extracts/isolation & purification , Plant Extracts/therapeutic use , Protein Kinase Inhibitors/isolation & purification , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Radiation-Sensitizing Agents/isolation & purification , Radiation-Sensitizing Agents/pharmacology , Radiation-Sensitizing Agents/therapeutic use , Receptors, Estrogen/biosynthesis
7.
Cancer Biol Ther ; 6(4): 504-9, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17457045

ABSTRACT

Scutellaria barbata, a Traditional Chinese Medicine native in southern China, has been widely used for treating liver diseases. In this study, the anti-proliferative effect of Pheophorbide a (Pa), an active component from S. barbata, was examined on a multi-drug resistant (MDR) human hepatoma cell line R-HepG2. Our study showed that Pa could significantly inhibit the growth of R-HepG2 cells with an IC50 value at 25.0 microM after 48 hours treatment. When compared with the parental HepG2 cells, Pa showed weak resistance to R-HepG2. Efflux of Pa out of R-HepG2 cells was not observed as its cellular uptake level showed no significant difference comparing with HepG2 cells. Interestingly, significant reduction of P-glycoprotein expression on Pa-treated R-HepG2 cells was found at both transcriptional and translational levels, leading to reduction of P-glycoprotein activity. In addition, mechanistic study elucidated that Pa induced cell cycle arrest at G2/M phase and inhibited the expressions of G2/M phase cell cycle regulatory proteins, cyclin-A1 and cdc2 in a dose-dependent manner.


Subject(s)
ATP Binding Cassette Transporter, Subfamily B, Member 1/antagonists & inhibitors , Carcinoma, Hepatocellular/metabolism , Chlorophyll/analogs & derivatives , Drug Resistance, Multiple/drug effects , Drug Resistance, Neoplasm/drug effects , Liver Neoplasms/metabolism , Scutellaria/chemistry , ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Carcinoma, Hepatocellular/genetics , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Chlorophyll/isolation & purification , Chlorophyll/pharmacology , Humans
8.
Planta Med ; 72(1): 28-33, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16450292

ABSTRACT

Scutellaria barbata has long been used as a Chinese medicine for the treatment of liver diseases such as hepatitis and hepatocellular carcinoma. In the present study, a bioassay-guided method was used to isolate the most active components from Scutellaria barbata. The anti-proliferative effects on human hepatoma HepG2 and Hep3B cells of each fraction at every stage of the purification were monitored. An active component, which is 97% pure by high performance liquid chromatographic analysis, was isolated. Based on nuclear magnetic resonance (NMR) and mass spectrophotometric (MS) analysis, this active component was identified to be pheophorbide a (C35H36N4O5). Mechanistic studies showed that pheophorbide a induced apoptosis in Hep3B cells, a viral-induced hepatoma cell line. However, it was found to be non-toxic in normal human liver cells WRL-68. DNA fragmentation, sub-G1 cell cycle arrest, as well as suppression of the anti-apoptotic protein Bcl-2, release of cytochrome c to the cytosol, and activation of pro-caspase 3 and pro-caspase 9 were observed when Hep3B cells were treated with 40 microg/mL (i. e., 67.5 microM) pheophorbide a for 48 hours. In conclusion, this is the first report describing the isolation of pheophorbide a from Scutellaria barbata using a bioassay-guided isolation method. The anti-proliferative activity and possible mechanisms of action of pheophorbide a on hepatoma Hep3B cells are also discussed.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Apoptosis/drug effects , Carcinoma, Hepatocellular/drug therapy , Chlorophyll/analogs & derivatives , Scutellaria/chemistry , Antineoplastic Agents, Phytogenic/analysis , Antineoplastic Agents, Phytogenic/therapeutic use , Blotting, Western , Cell Line, Tumor , Cell Proliferation/drug effects , Chemical Fractionation , Chlorophyll/analysis , Chlorophyll/pharmacology , Chlorophyll/therapeutic use , DNA Fragmentation , Flow Cytometry , Humans , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use
9.
J Cutan Med Surg ; 10(4): 166-9, 2006.
Article in English | MEDLINE | ID: mdl-17234114

ABSTRACT

BACKGROUND: Cutaneous atypical mycobacterial infections have been increasingly described in association with cosmetic and alternative procedures. OBJECTIVE: We report an outbreak of acupuncture-associated mycobacteriosis. Between April and December 2002, 32 patients developed cutaneous mycobacteriosis after visiting an acupuncture practice in Toronto, Canada. RESULTS: Of 23 patients whose lesions were biopsied, 6 (26.1%) had culture-confirmed infection with Mycobacterium abscessus. These isolates were genetically indistinguishable by amplified fragment length polymorphism. The median incubation period was 1 month. Of 24 patients for whom clinical information was available, 23 (95.8%) had resolution of their infection. All patients developed residual scarring or hyperpigmentation. CONCLUSION: Nontuberculous mycobacteria should be recognized as an emerging, but preventable, cause of acupuncture-associated infections.


Subject(s)
Acupuncture Therapy/adverse effects , Disease Outbreaks , Mycobacterium Infections, Nontuberculous/epidemiology , Mycobacterium Infections, Nontuberculous/etiology , Skin Diseases, Bacterial/epidemiology , Skin Diseases, Bacterial/etiology , Adult , Aged , Aged, 80 and over , Female , Humans , Infection Control/standards , Male , Middle Aged , Needles , Ontario/epidemiology , Retrospective Studies
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