Therapy and pharmacological properties of hydroxychloroquine and chloroquine in treatment of systemic lupus erythematosus, rheumatoid arthritis and related diseases

Nucleobase Level Information into the Folding of G-Quadruplex by Anti-inflammatory Drugs in the Absence of Salt

G-quadruplexes (G4s) in the telomere region are important targets for cancer therapy. Molecules that can fold and stabilize the telomere DNA sequences, even in the absence of salt, can be an exciting prospect for therapy purposes. Anti-inflammatory drugs hydroxychloroquine (HCQ) and chloroquine (CQ) have shown promising effects in cancer therapy and also in the different levels of trial stages. In this study, we have investigated the structure and stability of several natural and mutated telomeric sequences with anti-inflammatory drugs and their analogues in the absence of salts using the biophysical and docking methods to understand the role of the quartet and loop nucleobases of DNA along with the functional group of drugs responsible for triggering the folding of telomeric DNA sequences into G4. The findings indicate that the hydrogen bonding between the charged side chain with the guanine repeating unit associated with the quartet and the thymine in the terminal loops of telomere DNA is the main driving force for the folding of telomere DNA sequences into G4 induced by anti-inflammatory drugs. The data indicate that the adenine nucleobase in the loop of the telomere does not play any role in its folding process induced by HCQ and CQ.

Species differences in microsomal metabolism of hydroxychloroquine

Hydroxychloroquine (HCQ), a medication renowned for its anti-malarial and anti-autoimmune properties, is susceptible to drug-drug interactions (DDIs), particularly those involving cytochrome P450 enzymes (CYPs). The pharmacokinetic and metabolic profiles of HCQ across species are not well-characterized. In this study, we conducted a comparative analysis of HCQ metabolism and pharmacokinetics in human liver microsomes and those from various preclinical animal models. Metabolite profiling indicated that the mono-oxidized metabolite M5 was predominantly produced in microsomes from mouse (MLM), rats (RLM), dogs (DLM), and pigs (PLM). Conversely, two other oxidative metabolites, M4 and M6, were uniquely generated in PLM. Utilizing selective inhibitors of human CYP isoforms, we identified key enzymes in HLM that differ from those in other species. Furthermore, the metabolic pathways in HLM were distinct from those observed in other species. In HLM, two metabolic pathways have been identified, each comprising a two-step reaction. CYP2D6, CYP2C8, CYP3A4, and CYP1A1 are the key enzymes involved in HCQ metabolism, with HCQ demonstrating significant substrate inhibition of CYP2D6, CYP2C8, and CYP1A1. Our work shed a new light on selection of suitable experimental animal models for accurate evaluation of HCQ's in vivo processes and its potential in multi-drug regimens.

Probing the nucleobase-specific binding interaction of hydroxychloroquine sulfate with RNA and subsequent sequestration by a water-soluble molecular basket

A thorough understanding of the binding interactions of small molecules with genetic materials of the cell (DNA/RNA) has a persistent importance in pharmaceutical industries for the development of new drugs for treating various life-threatening ailments. Hydroxychloroquine sulfate (HCQS), an antimalarial drug, was potentially used for clinical trials with the hope of treating patients suffering from SARS-CoV-2 during the COVID-19 pandemic. Herein, we have extensively delineated the binding interactions of HCQS with RNA under physiological conditions using multi-spectroscopic and calorimetric approaches. Our results demonstrated that HCQS binds to RNA through the groove-binding mode in uridine- and cytidine-rich regions. The mode of binding was meticulously characterized by fluorescence quenching studies and circular dichroism spectroscopy, well complemented by other experiments. Our results obtained from isothermal titration calorimetry reveal the phenomenon of the release of bound water molecules when HCQS binds at the groove position of RNA, the process being entropically driven. Furthermore, we have employed the concept of host-guest chemistry for the sequestration of RNA-bound HCQS using a water-soluble, non-toxic, 4-sulfocalix[4]arene as a basket-type macrocyclic host. This investigation may be conducive to the development of safe RNA-based therapeutics like RNA-based vaccines that comprise small molecule-RNA interactions.

Neuropsychiatric Side Effects of Hydroxychloroquine in a Patient With Idiopathic Pulmonary Hemosiderosis

BACKGROUND

Idiopathic pulmonary hemosiderosis (IPH) is a rare interstitial lung disease. Glucocorticosteroids and hydroxychloroquine are the most commonly used treatments. Although neuropsychiatric side effects related to hydroxychloroquine use are seen in adult cases, only one paediatric patient has been reported in the literature.

CASE PRESENTATION

We report a case of a 6-year-old girl with IPH, who developed neuropsychiatric symptoms, including restlessness, confusion and myoclonic movements, after the therapeutic use of hydroxychloroquine.

CONCLUSION

With increasing knowledge and experience of interstitial lung disease, the use of hydroxychloroquine treatment is increasing. It is important to remember that hydroxychloroquine is a central nervous system stimulant, and neuropsychiatric side effects may be seen in children. This report highlights the importance of recognising potential neuropsychiatric side effects in paediatric patients using hydroxychloroquine, especially when combined with corticosteroids or other risk factors.

Hydroxychloroquine in patients with systemic lupus erythematosus: how much is enough?

OBJECTIVE

To assess the daily and weight-adjusted dosages of hydroxychloroquine (HCQ) and the effects on long-term remission in the Lupus-Cruces cohort.

METHODS

Observational study of routine clinical care data. We selected inception patients treated with HCQ with at least 5 years of follow-up. Prolonged remission was achieved when patients fulfilled definitions of remission in systemic lupus erythematosus remission criteria in five consecutive yearly visits. The associations between the weight-adjusted dose of HCQ during 5 years and prolonged remission were analysed. We also investigated the associations between prednisone doses, immunosuppressives (IS) and other antimalarial use with HCQ doses.

RESULTS

150 inception patients fulfilled the inclusion criteria. The mean starting dose of HCQ was 206 mg/day. The mean weight-adjusted starting dose of HCQ was 3.1 mg/kg/day with no patients treated with doses ≥5 mg/kg/day. Treatment with HCQ was maintained during the whole 5-year follow-up time in 147 patients (98%). The mean dose of HCQ during the 5-year follow-up was 194.6 mg/day (2.9 mg/kg/day). 108 patients (72%) were in prolonged remission. The mean weight-adjusted dose of HCQ per patient did not differ between those who did and did not achieve prolonged remission (2.9 vs 3 mg/kg/day, p=0.5). The dose of prednisone per patient (mean 2.3 mg/day during the 5-year follow-up) did not differ according to the weight-adjusted dose of HCQ. The mean weight-adjusted HCQ dose during the whole follow-up was the same in patients treated or not with IS or with mepacrine.

CONCLUSIONS

With the use of HCQ at stable doses of 200 mg/day (or 3.0-3.5 mg/kg/day) as the background therapy in patients with systemic lupus erythematosus, the majority of patients achieved prolonged remission.

KOH-modified biochar enhances nitrogen metabolism of the chloroquine phosphate-disturbed anammox: Physical binding, EPS modulation and versatile metabolic hierarchy

Chloroquine phosphate (CQ) poses strong biotoxicity on anammox process, and thus detoxifying is essential for the stable operation of anammox in treating CQ-bearing wastewater. Biochar has been proven to simultaneously detoxify pollutant and modulate nitrogen cycle in anammox by its shelter effect and electron exchange capacity (EEC) ability. To further improve the ability of biochar to promote the nitrogen metabolism of anammox, a KOH modification strategy was used to tailor a high-EEC biochar in this work. KOH modified biochar can bind CQ for detoxification driven by hydrogen bond, π-π interaction, and electrostatic interaction. Meanwhile, the EEC of modified biochar increased by 70 % than that of pristine biochar, thus improving nitrogen removal efficiency by 55.6 % and 9.5 % than CQ and BC group, respectively. Besides, the microorganism regulated by modified biochar produced more α-helix configuration, improving EPS barrier ability to CQ and sludge granulation. Lastly, metagenomic analysis revealed that modified biochar can stimulate the Wood-Ljungdahl pathway, increased the relative abundance of CODH from 0.74 % in CQ to 1.00 % in modified BC group. It favored the proliferation of autotrophic microorganisms, especially increased the relative abundance of anammox bacteria by 86.8 % than CQ group. This work will shed the light on integrating high-EEC biochar into anammox to cope with the micropollutants stress.

Innovative Lipid Nanoparticles Co-Delivering Hydroxychloroquine and siRNA for Enhanced Rheumatoid Arthritis Therapy

Background: Rheumatoid arthritis (RA) is a debilitating autoimmune disorder characterized by chronic inflammation and joint damage. Despite advancements in treatment, complete remission remains elusive. Methods: In this study, we introduce a novel lipid nanoparticle formulation co-delivering hydroxychloroquine (HCQ) and siRNA targeting TNF-α (siTNF-α) using microfluidic technology, marking the first use of such a combination for RA therapy. Results: In LPS-stimulated RAW 264.7 cells, the nanoparticles effectively reduced inflammatory markers. When administered via an intra-articular injection in a rat model, they significantly decreased joint inflammation and demonstrated good biological safety. Conclusions: This pioneering approach highlights the potential of lipid nanoparticles as a dual-delivery platform for enhanced RA treatment through targeted intra-articular administration.

Bioinformatics and systems-biology approach to identify common pathogenic mechanisms for COVID-19 and systemic lupus erythematosus

BACKGROUND

The Coronavirus disease 2019 (COVID-19) pandemic has brought a heavy burden to the world, interestingly, it shares many clinical symptoms with systemic lupus erythematosus (SLE). It is unclear whether there is a similar pathological process between COVID-9 and SLE. In addition, we don't know how to treat SLE patients with COVID-19. In this study, we analyse the potential similar pathogenesis between SLE and COVID-19 and explore their possible drug regimens using bioinformatics and systems biology approaches.

METHODS

The common differentially expressed genes (DEGs) were extracted from the COVID-19 datasets and the SLE datasets for functional enrichment, pathway analysis and candidate drug analysis.

RESULT

Based on the two transcriptome datasets between COVID-19 and SLE, 325 common DEGs were selected. Hub genes were identified by protein-protein interaction (PPI) analysis. few found a variety of similar functional changes between COVID-19 and SLE, which may be related to the pathogenesis of COVID-19. Besides, we explored the related regulatory networks. Then, through drug target matching, we found many candidate drugs for patients with COVID-19 only or COVID-19 combined with SLE.

CONCLUSION

COVID-19 and SLE patients share many common hub genes, related pathways and regulatory networks. Based on these common targets, we found many potential drugs that could be used in treating patient with COVID-19 or COVID-19 combined with SLE.

Pilot Trial of Hydroxychloroquine as Add-On Therapy in Patients With Membranous Nephropathy

Introduction

Kidney Disease Improving Global Outcomes guidelines indicate that glucocorticoids and immunosuppressants comprise the first therapeutic regimens after 4 to 6 months of treatment for high-risk primary membranous nephropathy (PMN). However, some patients cannot achieve complete or partial remission at 6 months. This study aimed to evaluate the efficacy of traditional immunotherapy combined with hydroxychloroquine (HCQ), a well-known immune regulator, in patients with PMN.

Methods

This was a single-center, open-label, prospective study. We recruited 72 patients with nephrotic syndrome and PMN proven by renal biopsy from May 2020 to June 2024. We compared changes in proteinuria, serum albumin levels, estimated glomerular filtration rate (eGFR), and relapse rate at 3, 6, 9, and 12 months follow-up in 41 patients who received glucocorticoid and immunosuppressant, and in 31 who received HCQ plus standard-of-care.

Results

Baseline characteristics showed no statistical significance between the 2 groups. However, the HCQ group showed significantly reduced proteinuria compared to standard-of-care group. A reduced proteinuria was seen at 6 months (1.2 [0.4-2.2] vs. 2.2 [1.0-3.8] g/d, P = 0.029) and the relapse rate with 12 months follow-up was also significantly decreased in the HCQ group compared to the standard-of-care group (3.7% vs. 23.3%, P = 0.033).

Conclusions

HCQ may serve as an effective add-on therapy for PMN.

Hospitalization after hydroxychloroquine initiation in patients with heart failure with preserved ejection fraction and autoimmune disease

BACKGROUND

Hydroxychloroquine (HCQ) reduces cardiovascular events among patients with autoimmune disorders and is being evaluated as a therapeutic option for populations with high-risk cardiovascular disease. However, recent studies have raised concerns about HCQ use and cardiovascular events.

OBJECTIVE

To assess the association of HCQ initiation with heart failure-related and all-cause hospitalizations among patients with heart failure and preserved ejection fraction (HFpEF).

METHODS

We conducted a cohort study of patients aged ≥18 years with diagnosed HFpEF and autoimmune disease using MarketScan Commercial and Medicare Supplemental databases (2007-2019). Patients were required to initiate HCQ after their first HFpEF diagnosis (HCQ users) or not (HCQ nonusers). For the patients in the HCQ users group, the first HCQ prescription date was assigned as the index date. Index date for the HCQ nonuser group was assigned by prescription-time distribution matching HCQ users, by utilizing the number of days from HFpEF diagnosis to the first HCQ prescription. After 1:≥3 propensity score (PS) matching, Cox proportional hazards regression models were used to compare HF-related and all-cause hospitalizations between users and nonusers.

RESULTS

After PS matching, 2229 patients (592 HCQ users and 1637 HCQ nonusers) were included. After controlling for covariates, patients who received HCQ had lower risks of HF-related hospitalization (adjusted hazard ratio, 0.44; 95% CI, 0.24-0.82) and all-cause hospitalization (adjusted hazard ratio, 0.69; 95% CI, 0.57-0.83) compared with patients not using HCQ.

CONCLUSIONS

Among patients with HFpEF and autoimmune disease, initiation of HCQ use was associated with a decreased risk of HF-related and all-cause hospitalizations.

Hydroxychloroquine blood concentrations and effects in Chinese patients with IgA nephropathy

BACKGROUND

Hydroxychloroquine (HCQ) is recommended for Chinese patients with immunoglobulin A nephropathy (IgAN). However, the relationship between HCQ blood concentration and the therapeutic effect for IgAN has not yet been defined. This study investigates the optimal and efficacious range of HCQ blood concentrations in Chinese patients with IgAN.

METHODS

Seventy-three patients with biopsy-proven IgAN who were at risk of progression were included in this study. Thirty-eight patients with IgAN were treated with HCQ plus an optimized renin-angiotensin-aldosterone system inhibitor (RAASi), and thirty-five patients received only RAASi. Blood HCQ concentration and 24-h proteinuria were examined at three and six months after treatment.

RESULTS

The baseline proteinuria levels were comparable between the RAASi and HCQ groups. The HCQ group had lower 24-h proteinuria than the RAASi group three months after treatment, though the difference was not significant (p = 0.38). After six months, the median proteinuria level was significantly lower in the HCQ group than in the RAASi group (p < 0.05). The percentage reduction in 24-h proteinuria in the HCQ group was greater than that in the RAASi group at three (p < 0.05) and six months (p < 0.05). Hydroxychlorquine blood concentration and efficacy were positively correlated at three months (r = 0.428, p < 0.05) and six months (r = 0.48, p < 0.05). Moreover, the optimal blood concentration of HCQ for three-month efficacy was 418.96 ng/mL and that for six-month efficacy was 582.48 ng/mL. No serious adverse events were reported during HCQ treatment.

CONCLUSIONS

Hydroxyhloroquine safely reduces proteinuria in Chinese patients with IgAN. The efficacy of HCQ is positively correlated with its blood concentration.

Elucidating the mechanisms and efficacy of antimalarial drugs in systemic lupus erythematosus

INTRODUCTION

Antimalarials (AMs) are old drugs with a wide range of beneficial effects in systemic lupus erythematosus (SLE) beyond the control of activity. The most recent debate is focused on defining the optimal doses to assure the best benefit/risk ratio.

AREAS COVERED

We have reviewed the pharmacological basis underlying the various therapeutic effects of AMs and the beneficial and toxic effects of HCQ, also discussing the role of mepacrine not only as a substitute in cases of maculopathy, but also as a very effective therapy combined with HCQ. We searched PubMed and Embase for articles published in English at any time. We used the terms "hydroxychloroquine" or "mepacrine" or "chloroquine" or "antimalarials", "pharmacokinetics", "efficacy", "remission", "toxicity", "adherence". We reviewed original research articles, large observational studies, systematic reviews, and expert consensus statements. Additionally, studies were identified through the assessment of the reference lists of the evaluated manuscripts.

EXPERT OPINION

We advocate for the widespread use of HCQ at stable doses of 200 mg/d (≤4 mg/kg/d for most patients) and also for the early combination therapy with mepacrine to assure a good control of SLE activity, and also a durable and safe use of these essential drugs for the management of SLE.

Photochemical direct alkylation of heteroarenes with alkanes, alcohols, amides, and ethers

Direct functionalization of heteroarenes with simple alkanes utilizing anthracene as a photoredox catalyst has been established. This approach provides a sustainable alternative, avoiding costly reagents or peroxides. The method demonstrates a broad substrate scope, enabling regioselective alkylation of various heteroarenes, including azoles, pyridines, quinolines, isoquinolones, and quinoxalinones under mild conditions. A range of alkyl sources, such as alkanes, ethers, dioxane, trioxane, alcohol, and alkylamides were viable substrates. A plausible catalytic cycle was proposed based on the preliminary mechanistic evidence.

Chloroquine: Rapidly withdrawing from first-line treatment of COVID-19

The COVID-19 outbreak has garnered significant global attention due to its impact on human health. Despite its relatively low fatality rate, the virus affects multiple organ systems, resulting in various symptoms such as palpitations, headaches, muscle pain, and hearing loss among COVID-19 patients and those recovering from the disease. These symptoms impose a substantial physical, psychological, and social burden on affected individuals. On February 15, 2020, the Chinese government advised incorporating antimalarial drugs into the guidelines issued by the National Health Commission of China for preventing, diagnosing, and treating COVID-19 pneumonia. We examine the adverse effects of Chloroquine (CQ) in treating COVID-19 complications to understand why it is no longer the primary treatment for the disease.

Challenges and Reflections on Pandemic Disinformation: The Case of Hydroxychloroquine and the Implications for Global Public Health

This text addresses the implications of misinformation during the COVID-19 pandemic, focusing on the use of hydroxychloroquine (HCQ) and other drugs based on a specific publication. The article titled "Deaths induced by compassionate use of hydroxychloroquine during the first COVID-19 wave: an estimate," published in 2024 in the journal Biomedicine and Pharmacotherapy, reveals 17 000 deaths associated with the inappropriate use of HCQ in 6 countries, excluding Brazil and India. The dissemination of ineffective drugs, the persistence in recommending HCQ in Brazil, and the lack of an effective response from academia underscore the fragility of public health systems under pressure. Transparent communication between the scientific community and the public is vital, particularly considering studies, such as the one published in Nature Communications in 2021, which warns of the risks of chloroquine. The text highlights the influence of social media in spreading unverified information and emphasizes the need for criminal liability for those contributing to the spread of misinformation. It concludes by underlining the importance of learning from past mistakes to build a more resilient and informed future in the field of public health.

Target in Sight: A Comprehensive Review of Hydroxychloroquine-Induced Bull's Eye Maculopathy

Purpose of Review

We review the latest screening and diagnostic techniques, and the most recent recommendations on the management of hydroxychloroquine retinopathy.

Recent Findings

Hydroxychloroquine (HCQ) has been shown to cause retinal toxicity in a dose-dependent fashion. Early diagnosis is critical as the resultant retinopathy is not reversible. New imaging modalities, such as adaptive optics (AO), microperimetry, and retro-mode imaging, may show promise in the timely diagnosis of HCQ retinopathy.

Summary

Automated visual fields and spectral-domain optical coherence tomography (SD-OCT) are the primary tests used in routine screening for HCQ retinopathy, but fundus autofluorescence (FAF) and multifocal electroretinogram (mfERG) have also been shown to be useful. A baseline ophthalmologic examination is recommended in all patients beginning long-term hydroxychloroquine therapy within the first year of starting therapy. Automated visual fields and SD-OCT should be included during this baseline exam in patients with pre-existing macular conditions. Afterwards, annual screening can be deferred for the first 5 years of HCQ treatment unless the patient has a major risk factor.

Association between geniquin therapy and the risk of developing periodontal disease in patients with primary Sjögren's syndrome: A population-based cohort study from Taiwan

Primary Sjögren's syndrome (pSS) is a chronic autoimmune disease that causes dysfunction of salivation and harmful oral conditions. The association between periodontal disease (PD) and pSS with or without geniquin therapy remains controversial. This study evaluated the association between geniquin therapy and the risk of subsequent development of PD in pSS patients. From Taiwan's National Health Insurance Research Database, we selected a control cohort of 106,818 pSS patients, followed up from 2000 to 2015, matched (1:4) by age and index year with 427,272 non-pSS patients. We also analyzed 15,149 pSS patients receiving geniquin therapy (cohort 1) and 91,669 pSS patients not receiving geniquin therapy (cohort 2). After adjusting for confounding factors, multivariate Cox proportional hazards regression analysis was used to compare the risk of PD over the 15-year follow-up. In the control cohort, 11,941 (11.2%) pSS patients developed PD compared to 39,797 (9.3%) non-pSS patients. In cohorts 1 and 2, 1,914 (12.6%) pSS patients receiving geniquin therapy and 10,027 (10.9%) pSS patients not receiving geniquin therapy developed PD. The adjusted hazard ratio (HR) for subsequent PD in pSS patients was 1.165 (95% confidence interval [CI] = 1.147-1.195, p < 0.001) and in pSS patients receiving geniquin therapy was 1.608 (95% CI = 1.526-1.702, p < 0.001). The adjusted HR for PD treatment was 1.843. Patients diagnosed with pSS showed an increased risk of developing subsequent PD and receiving PD treatment than patients without pSS, while pSS patients receiving geniquin therapy showed even higher risks.

GDF11 protects against mitochondrial-dysfunction-dependent NLRP3 inflammasome activation to attenuate osteoarthritis

INTRODUCTION

Osteoarthritis (OA) is a highly prevalent degenerative disease worldwide, and tumor necrosis factor (TNF-α) is closely associated with its development. Growth differentiation factor 11 (GDF11) has demonstrated anti-injury and anti-aging abilities in certain tissues; however, its regulatory role in OA remains unclear and requires further investigation.

OBJECTIVES

To identify whether GDF11 can attenuate osteoarthritis. To exploring the the potential mechanism of GDF11 in alleviating osteoarthritis.

METHODS

In this study, we cultured and stimulated mouse primary chondrocytes with or without TNF-α, analyzing the resulting damage phenotype through microarray analysis. Additionally, we employed GDF11 conditional knockout mice OA model to examine the relationship between GDF11 and OA. To investigate the target of GDF11's function, we utilized NLRP3 knockout mice and its inhibitor to verify the potential involvement of the NLRP3 inflammasome.

RESULTS

Our in vitro experiments demonstrated that endogenous overexpression of GDF11 significantly inhibited TNF-α-induced cartilage matrix degradation and inflammatory expression in chondrocytes. Furthermore, loss of GDF11 led to NLRP3 inflammasome activation, inflammation, and metabolic dysfunction. In an in vivo surgically induced mouse model, intraarticular administration of recombinant human GDF11 alleviated OA pathogenesis, whereas GDF11 conditional knockout reversed this effect. Additionally, findings from the NLRP3-knockout DMM mouse model revealed that GDF11 exerted its protective effect by inhibiting NLRP3.

CONCLUSION

These findings demonstrate the ability of GDF11 to suppress TNF-α-induced inflammation and cartilage degeneration by preventing mitochondrial dysfunction and inhibiting NLRP3 inflammasome activation, suggesting its potential as a promising therapeutic drug for osteoarthritis.

Hydroxychloroquine-induced cardiomyopathy: role of cardiac magnetic resonance for the diagnosis and follow-up of a very rare entity-a case report

Background

Hydroxychloroquine (HCQ) is a disease-modifying antirheumatic used in rheumatological diseases such as systemic lupus erythematosus. Long-term exposure to HCQ results in drug accumulation and predisposes to adverse effects.

Case summary

We present the case of a 45-year-old woman with long-term treatment with HCQ who presented to the Emergency Department with acute heart failure. Transthoracic echocardiogram, previously normal, showed severe biventricular hypertrophy and biventricular systolic dysfunction. Cardiac magnetic resonance (CMR) confirmed the previous findings and showed elevated native T1 and T2 values, elevated extracellular volume, and extensive mid-wall late gadolinium enhancement (LGE). Infiltrative cardiomyopathy was suspected, and endomyocardial biopsy performed. Light microscopy showed myocyte hypertrophy and vacuolar change and absence of lymphocytic inflammatory infiltrates. The diagnosis of HCQ-induced cardiomyopathy was established, and the drug was withdrawn. A CMR performed 1 year later showed normal systolic function of both ventricles and normalization of T2 values, reflecting resolution of myocardial oedema. However, severe hypertrophy, elevated native T1 values, and LGE persisted.

Discussion

Our case shows that although discontinuation of the drug stops the progression of the disease, established myocardial structural damage persists. Early diagnosis of this entity is therefore essential to improve prognosis.

Blockage of Autophagy for Cancer Therapy: A Comprehensive Review

The incidence and mortality of cancer are increasing, making it a leading cause of death worldwide. Conventional treatments such as surgery, radiotherapy, and chemotherapy face significant limitations due to therapeutic resistance. Autophagy, a cellular self-degradation mechanism, plays a crucial role in cancer development, drug resistance, and treatment. This review investigates the potential of autophagy inhibition as a therapeutic strategy for cancer. A systematic search was conducted on Embase, PubMed, and Google Scholar databases from 1967 to 2024 to identify studies on autophagy inhibitors and their mechanisms in cancer therapy. The review includes original articles utilizing in vitro and in vivo experimental methods, literature reviews, and clinical trials. Key terms used were "Autophagy", "Inhibitors", "Molecular mechanism", "Cancer therapy", and "Clinical trials". Autophagy inhibitors such as chloroquine (CQ) and hydroxychloroquine (HCQ) have shown promise in preclinical studies by inhibiting lysosomal acidification and preventing autophagosome degradation. Other inhibitors like wortmannin and SAR405 target specific components of the autophagy pathway. Combining these inhibitors with chemotherapy has demonstrated enhanced efficacy, making cancer cells more susceptible to cytotoxic agents. Clinical trials involving CQ and HCQ have shown encouraging results, although further investigation is needed to optimize their use in cancer therapy. Autophagy exhibits a dual role in cancer, functioning as both a survival mechanism and a cell death pathway. Targeting autophagy presents a viable strategy for cancer therapy, particularly when integrated with existing treatments. However, the complexity of autophagy regulation and the potential side effects necessitate further research to develop precise and context-specific therapeutic approaches.

Pharmacology Progresses and Applications of Chloroquine in Cancer Therapy

Chloroquine is a common antimalarial drug and is listed in the World Health Organization Standard List of Essential Medicines because of its safety, low cost and ease of use. Besides its antimalarial property, chloroquine also was used in anti-inflammatory and antivirus, especially in antitumor therapy. A mount of data showed that chloroquine mainly relied on autophagy inhibition to exert its antitumor effects. However, recently, more and more researches have revealed that chloroquine acts through other mechanisms that are autophagy-independent. Nevertheless, the current reviews lacked a comprehensive summary of the antitumor mechanism and combined pharmacotherapy of chloroquine. So here we focused on the antitumor properties of chloroquine, summarized the pharmacological mechanisms of antitumor progression of chloroquine dependent or independent of autophagy inhibition. Moreover, we also discussed the side effects and possible application developments of chloroquine. This review provided a more systematic and cutting-edge knowledge involved in the anti-tumor mechanisms and combined pharmacotherapy of chloroquine in hope of carrying out more in-depth exploration of chloroquine and obtaining more clinical applications.

Chloroquine regulates the lipopolysaccharide-induced inflammatory response in RAW264.7 cells

INTRODUCTION AND OBJECTIVES

Macrophage-induced inflammation plays a key role in defense against injury and harmful pathogens. Autophagy and the inflammatory response are associated; however, the relationship between the autophagy pathway and lipopolysaccharide (LPS)- induced inflammatory responses remains unknown. We aimed to determine the effect of autophagy on the LPS-induced myeloid differentiation factor 88 (MyD88)/nuclear transcription factor kB (NF-kB) pathway-mediated inflammatory response in RAW264.7 cells.

MATERIALS AND METHODS

To determine the effect of autophagy on the LPS-induced inflammatory response, using various in vitro assays, we determined the effect of autophagy inhibitors and inducers on the inflammatory response in RAW264.7 cells.

RESULTS

Chloroquine (CQ), an autophagy inhibitor, suppressed pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNFα) in LPS-stimulated RAW264.7 cells. CQ also affected inflammatory mediators such as myeloid differentiation factor 88 and NF-kB in LPS-stimulated RAW264.7 cells.

CONCLUSION

This study demonstrated that CQ regulates the LPS-induced inflammatory response in RAW264.7 cells. We propose that targeting the regulation of pro-inflammatory cytokine levels and inflammatory mediators using CQ is a promising therapeutic approach for preventing inflammatory injury. CQ serves as a potential therapeutic target for treating various inflammatory diseases.

Infectious Diseases Society of America Guidelines on the Treatment and Management of Patients With COVID-19 (September 2022)

There are many pharmacologic therapies that are being used or considered for treatment of coronavirus disease 2019 (COVID-19), with rapidly changing efficacy and safety evidence from trials. The objective was to develop evidence-based, rapid, living guidelines intended to support patients, clinicians, and other healthcare professionals in their decisions about treatment and management of patients with COVID-19. In March 2020, the Infectious Diseases Society of America (IDSA) formed a multidisciplinary guideline panel of infectious disease clinicians, pharmacists, and methodologists with varied areas of expertise to regularly review the evidence and make recommendations about the treatment and management of persons with COVID-19. The process used a living guideline approach and followed a rapid recommendation development checklist. The panel prioritized questions and outcomes. A systematic review of the peer-reviewed and grey literature was conducted at regular intervals. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the certainty of evidence and make recommendations. Based on the most recent search conducted on 31 May 2022, the IDSA guideline panel has made 32 recommendations for the treatment and management of the following groups/populations: pre- and postexposure prophylaxis, ambulatory with mild-to-moderate disease, and hospitalized with mild-to-moderate, severe but not critical, and critical disease. As these are living guidelines, the most recent recommendations can be found online at: https://idsociety.org/COVID19guidelines. At the inception of its work, the panel has expressed the overarching goal that patients be recruited into ongoing trials. Since then, many trials were conducted that provided much-needed evidence for COVID-19 therapies. There still remain many unanswered questions as the pandemic evolved, which we hope future trials can answer.

Crosstalk between Inflammation and Atherosclerosis in Rheumatoid Arthritis and Systemic Lupus Erythematosus: Is There a Common Basis?

Cardiovascular disease is the leading cause of morbidity and mortality in patients with rheumatoid arthritis and systemic lupus erythematosus. Traditional cardiovascular risk factors, although present in lupus and rheumatoid arthritis, do not explain such a high burden of early cardiovascular disease in the context of these systemic connective tissue diseases. Over the past few years, our understanding of the pathophysiology of atherosclerosis has changed from it being a lipid-centric to an inflammation-centric process. In this review, we examine the pathogenesis of atherosclerosis in systemic lupus erythematosus and rheumatoid arthritis, the two most common systemic connective tissue diseases, and consider them as emblematic models of the effect of chronic inflammation on the human body. We explore the roles of the inflammasome, cells of the innate and acquired immune system, neutrophils, macrophages, lymphocytes, chemokines and soluble pro-inflammatory cytokines in rheumatoid arthritis and systemic lupus erythematosus, and the roles of certain autoantigens and autoantibodies, such as oxidized low-density lipoprotein and beta2-glycoprotein, which may play a pathogenetic role in atherosclerosis progression.

Functional role of autophagy in testicular and ovarian steroidogenesis

Autophagy is an evolutionarily conserved cellular recycling process that maintains cellular homeostasis. Despite extensive research in endocrine contexts, the role of autophagy in ovarian and testicular steroidogenesis remains elusive. The significant role of autophagy in testosterone production suggests potential treatments for conditions like oligospermia and azoospermia. Further, influence of autophagy in folliculogenesis, ovulation, and luteal development emphasizes its importance for improved fertility and reproductive health. Thus, investigating autophagy in gonadal cells is clinically significant. Understanding these processes could transform treatments for endocrine disorders, enhancing reproductive health and longevity. Herein, we provide the functional role of autophagy in testicular and ovarian steroidogenesis to date, highlighting its modulation in testicular steroidogenesis and its impact on hormone synthesis, follicle development, and fertility therapies.

Hydroxychloroquine interaction with phosphoinositide 3-kinase modulates prostate cancer growth in bone microenvironment: In vitro and molecular dynamics based approach

Patients with advanced prostate cancer (PCa) are more likely to develop bone metastases. Tumor cells thrive in the bone microenvironment, interacting with osteoblasts and osteoclasts. Given the PI3K/AKT pathway's metastatic potential and signal integration's ability to modulate cell fates in PCa development, drugs targeting this system have great therapeutic promise. Hydroxychloroquine (HCQ) is an anti-malarial medication commonly used to treat clinical conditions such as rheumatology and infectious disorders. We explored the anti-neoplastic effect of HCQ on PC3 and C4-2B cell lines in the bone microenvironment. Interestingly, HCQ treatment substantially decreases the viability, proliferation, and migration potential of PCa cells in the bone microenvironment. HCQ induces apoptosis and cell cycle arrest, even in the presence of osteoblast-secreted factors. Mechanistically, HCQ inhibited the activity of the PI3K/AKT signaling pathway, which ultimately regulates the proliferation and migration of PCa cells in the bone. The binding energy for docking HCQ with PI3K was -6.7 kcal/mol, and the complex was stabilized by hydrogen bonds, hydrophobic forces, and van der Waals forces. Molecular simulations further validated the structural integrity of the HCQ-PI3K complex without altering PI3K's secondary structure. Our findings underscore the efficacy of HCQ as a potential therapeutic agent in treating PCa.

A Comprehensive and Practical Approach to the Management of Lupus Nephritis in the Current Era

Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE) and is one of the leading causes of morbidity and mortality in patients with SLE. It is estimated that up to 60% of individuals with SLE will develop LN, which can manifest at any stage of a patient's life; however, it commonly emerges early in the course of SLE and tends to exhibit a more aggressive phenotype in men compared to women. Black and Hispanic patients are more likely to progress to kidney failure than white patients. LN is characterized by kidney inflammation and chronic parenchymal damage, leading to impaired kidney function and potential progression to kidney failure. This article provides a comprehensive overview of the epidemiology, pathogenesis, clinical presentation, diagnosis, and management of LN, highlighting the importance of early recognition and treatment of LN to prevent progressive, irreversible kidney damage and improve patient outcomes. Additionally, the article discusses current and emerging therapies for LN, including traditional immunosuppressive agents, biological agents, and novel therapies targeting specific pathways involved in LN pathogenesis, to provide a practical guide for clinicians in properly diagnosing LN and determining a patient-centered treatment plan.

Balancing risks and benefits in the use of hydroxychloroquine and glucocorticoids in systemic lupus erythematosus

INTRODUCTION

Hydroxychloroquine (HCQ) and glucocorticoids (GCs) constitute the oldest and more used drugs in the treatment of systemic lupus erythematosus (SLE). Despite this long experience, both are still subject to a number of uncertainties, mainly regarding the dose.

AREAS COVERED

We review the main mechanisms of action, the clinical and toxic effects of HCQ and GCs and analyze the recommendations for the use of both in guidelines published since 2018. We offer a set of recommendations based on the pharmacology, mechanisms of action and clinical evidence.

EXPERT OPINION

HCQ is the backbone therapy for SLE, and a judicious use must be accomplished, using doses that allow a good control of lupus without compromising the safety of treatments very much prolonged over the time. Stable doses of 200 mg/day seem to accomplish both conditions. GCs should be used more judiciously, with methyl-prednisolone pulses as the main therapy for inducing rapid remission and doses ≤5-2.5 mg/day be never exceeded in long-term maintenance treatments.

Non-biologic immunosuppressive drugs for inflammatory and autoimmune skin diseases

Non-biologic immunosuppressive drugs, such as azathioprine, dapsone or methotrexate are fundamental treatment options for a wide range of autoimmune and chronic inflammatory skin diseases. Some of these drugs were initially used for malignancies (e.g., azathioprine or methotrexate) or infectious diseases (e.g., hydroxychloroquine or dapsone) but are nowadays mostly used for their immunosuppressive/immunomodulating action. Although dermatologists have years of clinical experience with these drugs, some of the mechanisms of action are not fully understood and are the subject of research. Although these drugs are commonly used, lack of experience or knowledge regarding their safety profiles and management leads to skepticism among physicians. Here, we summarize the mechanism of action and detailed management of adverse effects of the most commonly used immunosuppressive drugs for skin diseases. Furthermore, we discuss the management of these drugs during pregnancy and breastfeeding, as well as their interaction and handling during vaccination.

Nicht-Biologika-Immunsuppressiva bei entzündlichen und autoimmunen Hautkrankheiten: Non-biologic immunosuppressive drugs for inflammatory and autoimmune skin diseases

Nicht‐Biologika‐Immunsuppressiva wie Azathioprin, Dapson oder Methotrexat sind grundlegende Behandlungsmöglichkeiten für ein breites Spektrum von Autoimmunerkrankungen und chronisch‐entzündlichen Hauterkrankungen. Einige dieser Medikamente wurden ursprünglich bei malignen Erkrankungen (zum Beispiel Azathioprin oder Methotrexat) oder Infektionskrankheiten (zum Beispiel Hydroxychloroquin oder Dapson) eingesetzt, werden aber heute hauptsächlich wegen ihrer immunsuppressiven/immunmodulierenden Wirkung verwendet. Obwohl Dermatologen über jahrelange klinische Erfahrung mit diesen Arzneimitteln verfügen, sind einige der Wirkmechanismen noch nicht vollständig geklärt und noch Gegenstand der Forschung. Obwohl diese Medikamente häufig eingesetzt werden, führen mangelnde Erfahrung oder fehlendes Wissen über ihre Sicherheitsprofile und ihr Management zu einer skeptischen Haltung bei den Ärzten. Hier fassen wir den Wirkmechanismus und das detaillierte Management der Nebenwirkungen der am häufigsten verwendeten immunsuppressiven Medikamente für Hautkrankheiten zusammen. Darüber hinaus diskutieren wir den Umgang mit diesen Medikamenten während der Schwangerschaft und Stillzeit sowie ihre Wechselwirkung und Handhabung im Zusammenhang mit Impfungen.

The effects of hydroxychloroquine and its promising use in refractory obstetric antiphospholipid syndrome

Hydroxychloroquine (HCQ) is obtained by hydroxylation of chloroquine (CQ) and the first indication was malaria. Nowadays, HCQ is commonly used in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) with favorable results. Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombosis and/or pregnancy morbidity and persistent positivity of antiphospholipid antibodies. Around 20-30% of pregnant women with APS develop adverse pregnancy outcomes despite conventional treatment with aspirin and heparin, called refractory obstetric APS. Interestingly, HCQ has shown positive effects on top of the standard of care in some refractory obstetric APS patients. HCQ mechanisms of action in APS comprise its ability to bind sialic acid present in cell membranes, its capacity to block the binding of antiphospholipid antibodies to the cell and the induced increase of pH in extracellular and intracellular compartments. However, the precise mechanisms of HCQ in the specific situation of refractory APS still need to be fully clarified. Therefore, this review summarizes the known modulating effects of HCQ and CQ, their side effects and use in APS and different pathologies to understand the benefit effects and the mechanism of action of HCQ in refractory obstetric APS.

Accelerated hydroxychloroquine toxic retinopathy

PURPOSE

To report a case series of patients with retinal toxicity due to hydroxychloroquine (HCQ) within a short span of treatment.

METHODS

A retrospective review of case records of patients with accelerated HCQ toxicity within 1 year of starting the treatment was done. Systemic co-morbidities, details of HCQ treatment, details of ocular examination, and results of multimodal investigations were noted.

RESULTS

Nine patients (1 male, 8 females) with age ranging from 40 to 73 years (mean 54.2 ± 13.4 years) who showed accelerated HCQ toxicity were included. None had systemic conditions or drug history predisposing to early HCQ toxicity. The treatment duration ranged from 2 to 11 months and the cumulative HCQ dose ranged from 18 to 120 g (mean 45.0 ± 33.0 g). The visual acuity was normal in 8 (88.9%) patients and retinal evaluation was normal in 4 (44.4%). Optical coherence tomography was abnormal in 4 (44.4%). Six (66.6%) cases had reduced sensitivity in the parafoveal point on visual field testing. All 9 cases had multifocal electroretinographic changes diagnostic of HCQ toxicity. The HCQ treatment was stopped in 8 and continued with reduced dose in 1 patient. The mean duration of follow-up was 11.2 ± 9.6 months during which 5 patients showed improved mfERG and 1 patient had a stable mfERG. Visual fields improvement was noted in 2 cases.

CONCLUSIONS

Patients on HCQ need to be kept on regular monitoring with more frequent follow-ups to detect signs of early onset toxicity and prevent permanent visual impairment. mfERG is an important diagnostic tool for HCQ toxicity.

Effects of hydroxychloroquine therapy on choroidal volume and choroidal vascularity index

PURPOSE

To determine changes in choroidal volume (CV) and choroidal vascularity index (CVI) in patients on hydroxychloroquine (HCQ) therapy.

METHODS

Retrospective analysis of patients on HCQ therapy. CV and CVI were assessed below the central foveal region on spectral-domain optical coherence tomography using an automatic denoising and localization algorithm. CV and CVI were compared with age-matched controls. Regression analyses were performed to generate associations between CV and CVI with demographics and HCQ treatment parameters. Associations were assessed using a generalized estimating equation model adjusted for intra-subject inter-eye correlations.

RESULTS

A total of 137 adult patients (23 males and 114 females) were included. Mean age was 45.6 ± 13.7 years and most patients identified as Caucasian (79%). Total duration of HCQ therapy ranged from 3 months to 20 years. Daily HCQ intake varied from 150-600 mg (mean = 304 mg), while cumulative doses ranged from 18-2,800 g. At presentation, the median CV was 0.51 (IQR:0.356-0.747) mm, and median CVI was 0.559 (IQR:0.528-0.578). Increased cumulative HCQ dose was associated with decreased CV (p = 0.006). Compared to age-matched controls, CV, CVI, and luminal area were significantly lower in the study group (p = 0.0003, 0.0001, and 0.0002).

CONCLUSION

In this study, we present a novel analysis of key biomarkers which predate the occurrence of HCQ retinopathy. Choroidal volume and vascularity index are significantly reduced in patients on HCQ therapy, especially at higher cumulative doses. These findings suggest new tools to guide medical decision-making for patients receiving HCQ therapy for rheumatologic diseases.

Chloroquine and Chemotherapeutic Compounds in Experimental Cancer Treatment

Chloroquine (CQ) and its derivate hydroxychloroquine (HCQ), the compounds with recognized ability to suppress autophagy, have been tested in experimental works and in clinical trials as adjuvant therapy for the treatment of tumors of different origin to increase the efficacy of cytotoxic agents. Such a strategy can be effective in overcoming the resistance of cancer cells to standard chemotherapy or anti-angiogenic therapy. This review presents the results of the combined application of CQ/HCQ with conventional chemotherapy drugs (doxorubicin, paclitaxel, platinum-based compounds, gemcitabine, tyrosine kinases and PI3K/Akt/mTOR inhibitors, and other agents) for the treatment of different malignancies obtained in experiments on cultured cancer cells, animal xenografts models, and in a few clinical trials. The effects of such an approach on the viability of cancer cells or tumor growth, as well as autophagy-dependent and -independent molecular mechanisms underlying cellular responses of cancer cells to CQ/HCQ, are summarized. Although the majority of experimental in vitro and in vivo studies have shown that CQ/HCQ can effectively sensitize cancer cells to cytotoxic agents and increase the potential of chemotherapy, the results of clinical trials are often inconsistent. Nevertheless, the pharmacological suppression of autophagy remains a promising tool for increasing the efficacy of standard chemotherapy, and the development of more specific inhibitors is required.

Pyrrole: A Decisive Scaffold for the Development of Therapeutic Agents and Structure-Activity Relationship

An overview of pyrroles as distinct scaffolds with therapeutic potential and the significance of pyrrole derivatives for drug development are provided in this article. It lists instances of naturally occurring pyrrole-containing compounds and describes the sources of pyrroles in nature, including plants and microbes. It also explains the many conventional and modern synthetic methods used to produce pyrroles. The key topics are the biological characteristics, pharmacological behavior, and functional alterations displayed by pyrrole derivatives. It also details how pyrroles are used to treat infectious diseases. It describes infectious disorders resistant to standard treatments and discusses the function of compounds containing pyrroles in combating infectious diseases. Furthermore, the review covers the uses of pyrrole derivatives in treating non-infectious diseases and resistance mechanisms in non-infectious illnesses like cancer, diabetes, and Alzheimer's and Parkinson's diseases. The important discoveries and probable avenues for pyrrole research are finally summarized, along with their significance for medicinal chemists and drug development. A reference from the last two decades is included in this review.

Emerging Treatments for Childhood Interstitial Lung Disease

Childhood interstitial lung disease (chILD) is a large and heterogeneous group of disorders characterized by diffuse lung parenchymal markings on chest imaging and clinical signs such as dyspnea and hypoxemia from functional impairment. While some children already present in the neonatal period with interstitial lung disease (ILD), others develop ILD during their childhood and adolescence. A timely and accurate diagnosis is essential to gauge treatment and improve prognosis. Supportive care can reduce symptoms and positively influence patients' quality of life; however, there is no cure for many of the chILDs. Current therapeutic options include anti-inflammatory or immunosuppressive drugs. Due to the rarity of the conditions and paucity of research in this field, most treatments are empirical and based on case series, and less than a handful of small, randomized trials have been conducted thus far. A trial on hydroxychloroquine yielded good safety but a much smaller effect size than anticipated. A trial in fibrotic disease with the multitargeted tyrosine kinase inhibitor nintedanib showed similar pharmacokinetics and safety as in adults. The unmet need for the treatment of chILDs remains high. This article summarizes current treatments and explores potential therapeutic options for patients suffering from chILD.

Role of Bioactive Compounds, Novel Drug Delivery Systems, and Polyherbal Formulations in the Management of Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is an autoimmune disorder that generally causes joint synovial inflammation as well as gradual cartilage and degenerative changes, resulting in progressive immobility. Cartilage destruction induces synovial inflammation, including synovial cell hyperplasia, increased synovial fluid, and synovial pane development. This phenomenon causes articular cartilage damage and joint alkalosis. Traditional medicinal system exerts their effect through several cellular mechanisms, including inhibition of inflammatory mediators, oxidative stress suppression, cartilage degradation inhibition, increasing antioxidants and decreasing rheumatic biomarkers. The medicinal plants have yielded a variety of active constituents from various chemical categories, including alkaloids, triterpenoids, steroids, glycosides, volatile oils, flavonoids, lignans, coumarins, terpenes, sesquiterpene lactones, anthocyanins, and anthraquinones. This review sheds light on the utilization of medicinal plants in the treatment of RA. It explains various phytoconstituents present in medicinal plants and their mechanism of action against RA. It also briefs about the uses of polyherbal formulations (PHF), which are currently in the market and the toxicity associated with the use of medicinal plants and PHF, along with the limitations and research gaps in the field of PHF. This review paper is an attempt to understand various mechanistic approaches employed by several medicinal plants, their possible drug delivery systems and synergistic effects for curing RA with minimum side effects.

Whole blood hydroxychloroquine: Does genetic polymorphism of cytochrome P450 enzymes have a role?

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a wide range of clinical manifestations and multifactorial etiologies ranging from environmental to genetic. SLE is associated with dysregulated immunological reactions, with increased immune complex formation leading to end-organ damages such as lupus nephritis, cutaneous lupus, and musculoskeletal disorders. Lupus treatment aims to reduce disease activity, prevent organ damage, and improve long-term patient survival and quality of life. Antimalarial, hydroxychloroquine (HCQ) is used as a first-line systemic treatment for lupus. It has shown profound efficacy in lupus and its associated conditions. However, wide variation in terms of clinical response to this drug has been observed among this group of patients. This variability has limited the potential of HCQ to achieve absolute clinical benefits. Several factors, including genetic polymorphisms of cytochrome P450 enzymes, have been stipulated as key entities leading to this inter-individual variation. Thus, there is a need for more studies to understand the role of genetic polymorphisms in CYP450 enzymes in the clinical response to HCQ. Focusing on the role of genetic polymorphism on whole blood HCQ in lupus disorder, this review aims to highlight up-to-date pathophysiology of SLE, the mechanism of action of HCQ, and finally the role of genetic polymorphism of CYP450 enzymes on whole blood HCQ level as well as clinical response in lupus.

Hydroxychloroquine: Key therapeutic advances and emerging nanotechnological landscape for cancer mitigation

Hydroxychloroquine (HCQ) is a unique class of medications that has been widely utilized for the treatment of cancer. HCQ plays a dichotomous role by inhibiting autophagy induced by the tumor microenvironment (TME). Preclinical studies support the use of HCQ for anti-cancer therapy, especially in combination with conventional anti-cancer treatments since they sensitize tumor cells to drugs, potentiating the therapeutic activity. However, clinical evidence has suggested poor outcomes for HCQ due to various obstacles, including non-specific distribution, low aqueous solubility and low bioavailability at target sites, transport across tissue barriers, and retinal toxicity. These issues are addressable via the integration of HCQ with nanotechnology to produce HCQ-conjugated nanomedicines. This review aims to discuss the pharmacodynamic, pharmacokinetic and antitumor properties of HCQ. Furthermore, the antitumor performance of the nanoformulated HCQ is also reviewed thoroughly, aiming to serve as a guide for the HCQ-based enhanced treatment of cancers. The nanoencapsulation or nanoconjugation of HCQ with nanoassemblies appears to be a promising method for reducing the toxicity and improving the antitumor efficacy of HCQ.

Physical Chemistry of Chloroquine Permeation through the Cell Membrane with Atomistic Detail

We provide a molecular-level description of the thermodynamics and mechanistic aspects of drug permeation through the cell membrane. As a case study, we considered the antimalaria FDA approved drug chloroquine. Molecular dynamics simulations of the molecule (in its neutral and protonated form) were performed in the presence of different lipid bilayers, with the aim of uncovering key aspects of the permeation process, a fundamental step for the drug's action. Free energy values obtained by well-tempered metadynamics simulations suggest that the neutral form is the only permeating protomer, consistent with experimental data. H-bond interactions of the drug with water molecules and membrane headgroups play a crucial role for permeation. The presence of the transmembrane potential, investigated here for the first time in a drug permeation study, does not qualitatively affect these conclusions.

Retinal alterations in evaluation of rheumatoid arthritis with chloroquine treatment: A new approach

OBJECTIVE

To evaluate the effect of hydroxychloroquine on conjunctival and retinal microvascular density in rheumatoid arthritis (RA) patients.

METHODS

Ten healthy controls, 10 RA patients who had not been treated with hydroxychloroquine, and 10 RA patients who had been treated with chloroquine for more than 5 years were recruited. Optical coherence tomography (OCTA) was used to examine the conjunctival and superficial and deep retinal microvascular density and compared the differences in microvascular density between the three groups.

RESULTS

The vascular density in RA group in superficial microvascular was significantly lower than that in control group (p < 0.001). Compared with RA group, the chloroquine group showed statistically significantly lower microvascular (p < 0.001) and deep microvascular (p = 0.018). Superficial microvascular was positively correlated with conjunctival vessel density in RA patients (r = 0.868, p = 0.0048).

CONCLUSIONS

The use of chloroquine could further reduce the vascular density in the absence of statistical difference in the course of the disease.

Biotransformation research advances - 2022 year in review

This annual review is the eighth of its kind since 2016 (Baillie et al. 2016, Khojasteh et al. 2017, Khojasteh et al. 2018, Khojasteh et al. 2019, Khojasteh et al. 2020, Khojasteh et al. 2021, Khojasteh et al. 2022). Our objective is to explore and share articles which we deem influential and significant in the field of biotransformation.

Hydroxychloroquine in nephrology: current status and future directions

Hydroxychloroquine is one of the oldest disease-modifying anti-rheumatic drugs in clinical use. The drug interferes with lysosomal activity and antigen presentation, inhibits autophagy, and decreases transcription of pro-inflammatory cytokines. Owing to its immunomodulatory, anti-inflammatory, anti-thrombotic effect, hydroxychloroquine has been an integral part of therapy for systemic lupus erythematosus and lupus nephritis for several decades. The therapeutic versatility of hydroxychloroquine has led to repurposing it for other clinical conditions, with recent studies showing reduction in proteinuria in IgA nephropathy. Research is also underway to investigate the efficacy of hydroxychloroquine in primary membranous nephropathy, Alport's syndrome, systemic vasculitis, anti-GBM disease, acute kidney injury and for cardiovascular risk reduction in chronic kidney disease. Hydroxychloroquine is well-tolerated, inexpensive, and widely available and therefore, should its indications expand in the future, it would certainly be welcomed. However, clinicians should be aware of the risk of irreversible and progressive retinal toxicity and rarely, cardiomyopathy. Monitoring hydroxychloroquine levels in blood appears to be a promising tool to evaluate compliance, individualize the dose and reduce the risk of retinal toxicity, although this is not yet standard clinical practice. In this review, we discuss the existing knowledge regarding the mechanism of action of hydroxychloroquine, its utility in lupus nephritis and other kidney diseases, the main adverse effects and the evidence gaps that need to be addressed in future research. Created with Biorender.com. HCQ, hydroxychloroquine; GBM, glomerular basement membrane; mDC, myeloid dendritic cell; MHC, major histocompatibility complex; TLR, toll-like receptor.

Alkanes in Minisci-Type Reaction under Photocatalytic Conditions with Hydrogen Evolution

We report herein a protocol for the selective activation of C(sp3)-H bonds based on the interplay of two readily available organic catalysts and their successful implementation in cross-coupling azaarenes with alkanes. This Minisci-like reaction is promoted by visible light at room temperature and is free from chemical oxidants, metals, and chlorinated solvents. A wide range of substrates are compatible, including some bioactive molecules. Mechanistic studies support a dual catalytic cycle with H2 evolution.

Systemic Sclerosis with Inflammatory Myositis: A Case Report

The overlap of systemic sclerosis and inflammatory myositis is a rare disorder which results in immune system activation and production of autoantibodies. We present a case of a 28-year-old female with complaints of generalized weakness, multiple joint pain, facial puffiness, and blackish discolouration of skin over the last 4 months. Blood investigations demonstrated autoantibodies positive for overlap syndrome. She was managed with hydroxychloroquine, mycophenolate mofetil and steroids. This case report highlights the importance of early diagnosis and treatment of this rare entity for better patient outcomes.

Keywords

antibodies; case reports; inflammation; systemic sclerosis.

Targeted co-delivery of methotrexate and chloroquine via a pH/enzyme-responsive biocompatible polymeric nanohydrogel for colorectal cancer treatment

Application of conventional chemotherapy regardless of its unique effectiveness have been gradually being edged aside due to limited targeting capability, lack of selectivity and chemotherapy-associated side effects. To this end, colon-targeted nanoparticles via combination therapy have shown great therapeutic potential against cancer. Herein, pH/enzyme-responsive biocompatible polymeric nanohydrogels based on poly(methacrylic acid) (PMAA) containing methotrexate (MTX) and chloroquine (CQ) were fabricated. PMAA-MTX-CQ exhibited high drug loading capacity of which MTX was 4.99% and was CQ 25.01% and displayed pH/enzyme-triggered drug release behavior. Higher CQ release rate (76%) under simulated acidic microenvironment of tumor tissue whereas 39% of CQ was released under normal physiological conditions. Intestinally, MTX release was facilitated in the presence of proteinase K enzyme. TEM image demonstrated spherical morphology with particle size of less than 50 nm. In vitro and in vivo toxicity assessments indicated that developed nanoplatforms possessed great biocompatibility. These nanohydrogels did not cause any adverse effects against Artemia Salina and HFF2 cells (around 100% cell viability) which highlight the safety of prepared nanohydrogels. There was no death in mice received different concentrations of nanohydrogel through oral administration and less than 5% hemolysis was found in red blood cells incubated with PMAA nanohydrogels. In vitro anti-cancer results showed that combination therapy based on PMAA-MTX-CQ can effectively suppress the growth of SW480 colon cancer cells (29% cell viability) compared to monotherapy. Altogether, these findings suggest that pH/enzyme-responsive PMAA-MTX-CQ could effectively inhibit cancer cell growth and progression via site-specific delivery of its cargo in a safe and controlled manner.

Pharmacokinetics of hydroxychloroquine in Japanese systemic lupus erythematosus patients with renal impairment

OBJECTIVES

Reduction of the hydroxychloroquine (HCQ) dosage is recommended in systemic lupus erythematosus (SLE) patients with renal impairment, but a pharmacokinetics (PK) study of patients with renal impairment has not yet been performed.

METHODS

We investigated the PK of both single and multiple doses of HCQ and its metabolites in SLE patients with renal impairment who newly started HCQ at a daily dose of 300 mg based on an ideal body weight dosage of 6.5 mg/kg. Population PK analysis was performed using a non-linear mixed-effects model.

RESULTS

In total, 219 samples from 21 patients were analysed. The PK of HCQ in blood after single and multiple oral administrations followed the two-compartment model. At steady state, the concentration ratio of HCQ to each metabolite was HCQ:desethylhydroxychloroquine:desethylchloroquine:bisdesethylchloroquine = 1:0.28:0.1:0.06. The HCQ concentration correlated positively with that of each metabolite. The estimated values (relative standard error) of the population PK parameters were the total clearance at 110 l/h (31%) and a central volume of distribution of 398 l (19%). Co-administration of prednisolone and age, but not renal impairment, were factors affecting the total clearance of HCQ.

CONCLUSIONS

From the PK perspective, a dosage reduction is unnecessary in SLE patients with impaired renal function.

Antimalarial Drugs Induce the Selective Folding of Human Telomeric G-Quadruplex in a Cancer-Mimicking Microenvironment

Regulating the equilibrium between the duplex form of DNA and G-quadruplex (Gq) and stabilizing the folded Gq are the critical factors for any drug to be effective in cancer therapy due to the direct involvement of Gq in controlling the transcription process. Antimalarial drugs are in the trial stage for different types of cancer diseases; however, the plausible mechanism of action of these drug molecules is not well known. Hence, we investigate the plausible role of antimalarial drugs in the folding and stabilization of Gq-forming DNA sequences from the telomere and promoter gene regions by varying the salt (KCl) concentrations, mimicking the in vitro cancerous and normal cell microenvironments. The study reveals that antimalarial drugs fold and stabilize specifically to telomere Gq-forming sequences in the cancerous microenvironment than the DNA sequences located in the promoter region of the gene. Antimalarial drugs are not only able to fold Gq but also efficiently protect them from unfolding by their complementary strands, hence significantly biasing the equilibrium toward the Gq formation from the duplex. In contrast, in a normal cell microenvironment, K+ controls the folding of telomeres, and the role of antimalarial drugs is not prominent. This study suggests that the action of antimalarial drugs is sensitive to the cancer microenvironment as well as selective to the Gq-forming region.

Hydroxychloroquine reduces T cells activation recall antigen responses

BACKGROUND

In the context of the current COVID-19 pandemic, there is still limited information about how people suffering from autoimmune diseases respond to the different COVID vaccines. The fact that they are taking an immunosuppressant or other drugs that aim to decrease the immune system activities, such as hydroxychloroquine (HCQ), could also impact their ability to respond to a COVID vaccine and vaccines in general.

METHODS

Heathy donors were given 200mg of HCQ daily for 6-weeks to assess HCQs impact on the systemic T cells and humoral immune response. Peripheral blood mononuclear cells (PBMC) and plasma were obtained at baseline and 6-weeks after starting daily HCQ. Flow cytometry assays were designed to determine changes in T cell activation and T cell responses. Bead array multiplex were used to analyse antibodies and cytokine levels before and after HCQ intake.

RESULTS

As anticipated, HCQ treatment decreased ex vivo T cell activation. We observed a decrease in CD4+CD161- expressing CCR5 (p = 0.015) and CD69 (p = 0.004) as well as in CD8+CCR5+ (p = 0.003), CD8+CD161+CCR5+ (p = 0.002) and CD8+CD161+CD95+ (p = 0.004). Additionally, HCQ decreased the proportion of Th17 expressing CD29 (p = 0.019), a subset associated with persistent inflammation. The proportion of T regulatory cells expressing the inhibitory molecule TIGIT was also reduced by HCQ (p = 0.003). As well, T cells from people on HCQ were less responsive to activation and cytokine production following stimulation with recall antigens and memory T cells were less likely to produce both IFNγ and TNFα following stimulation.

CONCLUSION

This study shows HCQ is associated with lower T cell activation and decreased T cell cytokine production. While this study was not performed with the intent of looking at COVID vaccine response, it does provide important information about the changes in immune response that may occur in patient taking HCQ as a treatment for their autoimmune disease.