High Antiplasmodial Activity of Golden Gamat (S.hermanni) Extract Through In Vitro Study

S.hermanni is a marine biota that contains active components that are anti-fungal, anti-bacterial, antioxidant, anti-inflammatory, and anti-cancer. The research focused on examining the antiplasmodial activity of an ethanol extract of S. hermanni on the proliferation of P. falciparum in vitro. The total sample size was 30 mediums, which included: (G1). No extract or chloroquine administration in the P.falciparum medium (G2). Chloroquine treatment administration on P. falciparum medium (G3). P. falciparum medium with S. hermanni extract. Parasitaemia, growth percentage, inhibitory rate, and IC50 were among the parameters evaluated. Administration of extract serial doses succeeds in reducing the percentage of parasite growth and parasitemia levels. G3 demonstrated an inhibitory rate of 88.51 % with a dose of 100 µg/ml and an IC50 of 2.86 µg/ml, indicating high antimalarial activity, although chloroquine had greater antimalarial activity than S. hermanni extract. In vitro studies on S hermanni, ethanol extract indicated that it contains bioactive components and can be an effective antiplasmodial agent.

The role of conspiracy beliefs for COVID-19 prevention: A meta-analysis

While conspiracy theories about COVID-19 are proliferating, their impact on health-related responses during the present pandemic is not yet fully understood. We meta-analyzed correlational and longitudinal evidence from 53 studies (N = 78,625) conducted in 2020 and 2021, demonstrating under what conditions COVID-19 conspiracy beliefs influence prevention responses. Conspiracy beliefs were associated with reluctance toward prevention measures both cross-sectionally and over time. They primarily reduced high-effort and pervasive responses (vaccination, social distancing), whereas low-effort responses (wearing masks, hygiene) seemed unaffected. Alarmingly, conspiracy beliefs had an increasing effect on prevention responses as the pandemic progressed and predicted support for alternative treatments that lack a scientific basis (e.g., chloroquine treatment, complementary medicine). Conspiracy beliefs are a non-negligeable and growing threat to public health.

Changes Associated with Treatment of Plasmodium berghei Infected Mice with Momordica charantia, Xylopia aethiopica and Entandrophragma angolense Leaf Extract

Aim: Leaves of plants have been useful in the treatment of various diseases and infections. The study aims at determining the nephrotoxicity, hepatotoxicity, and hematological effect of Momordica charantia, Xylopia aethiopica, and Entandrophragma angolense on the Plasmodium berghei infected mice. Study Design: The plants’ leaves were air-dried and extracted. Forty-two Swiss male mice, 18 to 25 g, were grouped into six of seven mice each. Group I was uninfected but were administered with normal saline for four days, Group II to VI were all infected with P. berghei and administered with normal saline, 300 mg/b.w. of M. charantia leaf extract, 300 mg/b.w. of E. angolense leaf extract, 300 mg/b.w. of X. aethiopica leaf extract and 40 mg/b.w. of chloroquine injection for four days, respectively. Results: The treatment groups showed a lower level of toxicity when compared with chloroquine treatment. X. aethiopica has the greatest positive impact on the PCV level of the experimental animals of its treated group compared with other groups. Conclusion: Our findings confirmed the antimalarial potential of X. aethiopica and thus can be used to treat malaria without anemia as a side effect.

Decreased prevalence of the Plasmodium falciparum Pfcrt K76T and Pfmdr1 and N86Y mutations post-chloroquine treatment withdrawal in Katete District, Eastern Zambia

Background In 2002, Zambia withdrew chloroquine as first-line treatment for Plasmodium falciparum malaria due to increased treatment failure and worldwide spread of chloroquine resistance. The artemisinin combination regimen, artemether–lumefantrine, replaced chloroquine (CQ) as first choice malaria treatment. The present study determined the prevalence of CQ resistance molecular markers in the Pfcrt and Pfmdr1 genes in Eastern Zambia at 9 and 13 years after the removal of drug pressure. Methods Samples collected from Katete District during the drug therapeutic efficacy assessments conducted in 2012 and 2016 were assayed by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) to determine the prevalence of genetic mutations, K76T on the Pfcrt gene and N86Y on the Pfmdr1 gene. A total of 204 P. falciparum-positive DBS samples collected at these two time points were further analysed. Results Among the samples analysed for Pfcrt K76T and Pfmdr1 N86Y in the present study, 112 (82.4%) P. falciparum-infected samples collected in 2012 were successfully amplified for Pfcrt and 94 (69.1%) for Pfmdr1, while 69 (65.7%) and 72 (68.6%) samples from 2016 were successfully amplified for Pfcrt and Pfmdr1, respectively. In 2012, the prevalence of Pfcrt 76K (sensitive) was 97.3%, 76T (resistant) was 1.8%, and 0.8% had both 76K and 76T codons (mixed). Similarly in 2012, the prevalence of Pfmdr1 86N (sensitive) was 97.9% and 86Y (resistant) was 2.1%. In the 2016 samples, the prevalence of the respective samples was 100% Pfcrt 76K and Pfmdr1 86N. Conclusion This study shows that there was a complete recovery of chloroquine-sensitive parasites by 2016 in Katete District, Eastern Zambia, 13 years following the withdrawal of CQ in the country. These findings add to the body of evidence for a fitness cost in CQ-resistant P. falciparum in Zambia and elsewhere. Further studies are recommended to monitor resistance countrywide and explore the feasibility of integration of the former best anti-malarial in combination therapy in the future.

Knockdown of PEX16 Induces Autophagic Degradation of Peroxisomes

Peroxisome abundance is regulated by homeostasis between the peroxisomal biogenesis and degradation processes. Peroxin 16 (PEX16) is a peroxisomal protein involved in trafficking membrane proteins for de novo peroxisome biogenesis. The present study demonstrates that PEX16 also modulates peroxisome abundance through pexophagic degradation. PEX16 knockdown in human retinal pigment epithelial-1 cells decreased peroxisome abundance and function, represented by reductions in the expression of peroxisome membrane protein ABCD3 and the levels of cholesterol and plasmalogens, respectively. The activation of pexophagy under PEX16 knockdown was shown by (i) abrogated peroxisome loss under PEX16 knockdown in autophagy-deficient ATG5 knockout cell lines, and (ii) increased autophagy flux and co-localization of p62—an autophagy adaptor protein—with ABCD3 in the presence of the autophagy inhibitor chloroquine. However, the levels of cholesterol and plasmalogens did not recover despite the restoration of peroxisome abundance following chloroquine treatment. Thus, PEX16 is indispensable for maintaining peroxisome homeostasis by regulating not only the commonly known biogenesis pathway but also the autophagic degradation of peroxisomes.

Therapeutic Approach of KRAS Mutant Tumours by the Combination of Pharmacologic Ascorbate and Chloroquine

The Warburg effect has been considered a potential therapeutic target to fight against cancer progression. In KRAS mutant cells, PKM2 (pyruvate kinase isozyme M2) is hyper-activated, and it induces GLUT1 expression; therefore, KRAS has been closely involved in the initiation of Warburg metabolism. Although mTOR (mammalian target of rapamycin), a well-known inhibitor of autophagy-dependent survival in physiological conditions, is also activated in KRAS mutants, many recent studies have revealed that autophagy becomes hyper-active in KRAS mutant cancer cells. In the present study, a mathematical model was built containing the main elements of the regulatory network in KRAS mutant cancer cells to explore the further possible therapeutic strategies. Our dynamical analysis suggests that the downregulation of KRAS, mTOR and autophagy are crucial in anti-cancer therapy. PKM2 has been assumed to be the key switch in the stress response mechanism. We predicted that the addition of both pharmacologic ascorbate and chloroquine is able to block both KRAS and mTOR pathways: in this case, no GLUT1 expression is observed, meanwhile autophagy, essential for KRAS mutant cancer cells, is blocked. Corresponding to our system biological analysis, this combined pharmacologic ascorbate and chloroquine treatment in KRAS mutant cancers might be a therapeutic approach in anti-cancer therapies.

Mortality outcomes with hydroxychloroquine and chloroquine in COVID-19 from an international collaborative meta-analysis of randomized trials

Substantial COVID-19 research investment has been allocated to randomized clinical trials (RCTs) on hydroxychloroquine/chloroquine, which currently face recruitment challenges or early discontinuation. We aim to estimate the effects of hydroxychloroquine and chloroquine on survival in COVID-19 from all currently available RCT evidence, published and unpublished. We present a rapid meta-analysis of ongoing, completed, or discontinued RCTs on hydroxychloroquine or chloroquine treatment for any COVID-19 patients (protocol: https://osf.io/QESV4/). We systematically identified unpublished RCTs (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform, Cochrane COVID-registry up to June 11, 2020), and published RCTs (PubMed, medRxiv and bioRxiv up to October 16, 2020). All-cause mortality has been extracted (publications/preprints) or requested from investigators and combined in random-effects meta-analyses, calculating odds ratios (ORs) with 95% confidence intervals (CIs), separately for hydroxychloroquine and chloroquine. Prespecified subgroup analyses include patient setting, diagnostic confirmation, control type, and publication status. Sixty-three trials were potentially eligible. We included 14 unpublished trials (1308 patients) and 14 publications/preprints (9011 patients). Results for hydroxychloroquine are dominated by RECOVERY and WHO SOLIDARITY, two highly pragmatic trials, which employed relatively high doses and included 4716 and 1853 patients, respectively (67% of the total sample size). The combined OR on all-cause mortality for hydroxychloroquine is 1.11 (95% CI: 1.02, 1.20; I² = 0%; 26 trials; 10,012 patients) and for chloroquine 1.77 (95%CI: 0.15, 21.13, I² = 0%; 4 trials; 307 patients). We identified no subgroup effects. We found that treatment with hydroxychloroquine is associated with increased mortality in COVID-19 patients, and there is no benefit of chloroquine. Findings have unclear generalizability to outpatients, children, pregnant women, and people with comorbidities.

Decreased Prevalence of the Plasmodium Falciparum Pfcrt K76T and Pfmdr1 N86Y Mutations Post- Chloroquine Treatment Withdrawal in Katete District, Eastern Zambia

Background: In 2002, Zambia withdrew chloroquine as first line treatment for Plasmodium falciparum malaria due to increased treatment failure and world-wide spread of chloroquine resistance. The artemisinin combination regimen artemether-lumefantrine replaced chloroquine as first choice malaria treatment. The present study determined the prevalence of chloroquine resistance molecular markers in the malaria parasite Pfcrt and Pfmdr1 genes in Eastern Zambia at nine and thirteen years after the removal of drug pressure.Methods: We assayed by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) the prevalence of the genetic mutations, K76T on the Pfcrt gene and N86Y on the Pfmdr1 gene in samples collected from Katete District during drug therapeutic efficacy assessments conducted in 2012 and 2016.Results: A total of 204 P. falciparum positive samples from 2012 and 2016 were further analysed for Pfcrt K76T and Pfmdr1 N86Y. 112 P. falciparum infected samples collected in 2012 were successfully amplified for Pfcrt and Pfmdr1, while 69 (65.7%) and 72 (68.6%) samples from 2016 were successfully amplified for Pfcrt and Pfmdr1. In 2012, the prevalence of Pfcrt 76K was 97.3%, 76T was 1.8%, and 0.8% had both 76K and 76T codons. The prevalence of Pfmdr1 86N was 97.9% and 86Y was 2.1%. In the 2016 samples, the prevalence of the respective parasite genotypes was 100% Pfcrt 76K and Pfmdr1 86N.Conclusion: This study shows that there was a complete recovery of chloroquine-sensitive parasites by 2016 in Katete District, thirteen years following the withdrawal of CQ. These findings add to the body of evidence for a fitness cost in chloroquine-resistant P. falciparum in Zambia and elsewhere. Further studies are recommended to explore the feasibility of integration of the former best antimalarial in combination therapy in the future.

The infantile myofibromatosis NOTCH3 L1519P mutation leads to hyperactivated ligand-independent Notch signaling and increased PDGFRB expression

ABSTRACTInfantile myofibromatosis (IMF) is a benign tumor form characterized by the development of nonmetastatic tumors in skin, bone, muscle and sometimes viscera. Autosomal-dominant forms of IMF are caused by mutations in the PDGFRB gene, but a family carrying a L1519P mutation in the NOTCH3 gene has also recently been identified. In this study, we address the molecular consequences of the NOTCH3L1519P mutation and the relationship between Notch and PDGFRB signaling in IMF. The NOTCH3L1519P receptor generates enhanced downstream signaling in a ligand-independent manner. Despite the enhanced signaling, the NOTCH3L1519P receptor is absent from the cell surface and instead accumulates in the endoplasmic reticulum. Furthermore, the localization of the NOTCH3L1519P receptor in the bipartite, heterodimeric state is altered, combined with avid secretion of the mutated extracellular domain from the cell. Chloroquine treatment strongly reduces the amount of secreted NOTCH3L1519P extracellular domain and decreases signaling. Finally, NOTCH3L1519P upregulates PDGFRB expression in fibroblasts, supporting a functional link between Notch and PDGF dysregulation in IMF. Collectively, our data define a NOTCH3–PDGFRB axis in IMF, in which an IMF-mutated NOTCH3 receptor elevates PDGFRB expression. The functional characterization of a ligand-independent gain-of-function NOTCH3 mutation is important for Notch therapy considerations for IMF, including strategies aimed at altering lysosome function.