Shahid Siddiqui

Regulation of fat storage and reproduction by Kruppel-like transcription factor KLF3 and fat-associated genes in Caenorhabditis elegans.

Coordinated regulation of fat storage and utilization is essential for energy homeostasis, and its disruption is associated with metabolic syndrome and atherosclerosis in humans. Across species, Krüppel-like transcription factors (KLFs) have been identified as key components of adipogenesis. In humans, KLF14 acts as a master transregulator of adipose gene expression in type 2 diabetes and cis-acting expression quantitative trait locus associated with high-density lipoprotein cholesterol. Herein we report that, in Caenorhabditis elegans, mutants in klf-3 accumulate large fat droplets rich in neutral lipids in the intestine; this lipid accumulation is associated with an increase in triglyceride levels. The klf-3 mutants show normal pharyngeal pumping; however, they are sterile or semisterile. We explored important genetic interactions of klf-3 with the genes encoding enzymes involved in fatty acid (FA) β-oxidation in mitochondria or peroxisomes and FA synthesis in the cytosol, namely acyl-CoA synthetase (acs-1 and acs-2), acyl-CoA oxidase (F08A8.1 and F08A8.2), and stearoyl-CoA desaturase (fat-7). We show that mutations or RNA interference in these genes increases fat deposits in the intestine of acs-1, acs-2, F08A8.1, and F08A8 animals. We further show that acs-1 and F08A8.1 influence larval development and fertility, respectively. Thus, KLF3 may regulate FA utilization in the intestine and reproductive tissue. We demonstrate that depletion of F08A8.1 activity, but not of acs-1, acs-2, F08A8.2, or fat-7 activity, enhances the fat phenotype of the klf-3 mutant. Taken together, these results suggest that klf-3 regulates lipid metabolism, along with acs-1, acs-2, F08A8.1, and F08A8.2, by promoting FA β-oxidation and, in parallel, may contribute to normal reproductive behavior and fecundity in C. elegans.

C. elegans as a model organism for in vivo screening in cancer: Effects of human c-Met in lung cancer affect C. elegans vulva phenotypes

Cancers typically harbour several mutant forms of key cellular genes that contribute to its complex phenotype. Our lab has previously identified gain-of-function mutations in some of the receptor tyrosine kinases such as c-Met in lung cancer. In order to investigate the mutant gene in the context of a whole organism, the current choice of in vivo model is limited to the mouse. To rapidly screen the functional aspects of mutant forms of c-Met detected in lung cancer, we used the nematode C. elegans as the model organism. Transgenic worms were generated that harbour wild type or the frequently seen mutant forms of c-Met in lung cancer (c-MetR988C and c-MetT1010I). Expression of the mutant human c-Met forms in C. elegans consistently resulted in significantly low fecundity and abnormal vulval development characterized by hyperplasia. Interestingly, exposure of c-Met mutant transgenic worms to nicotine resulted in enhanced abnormal vulval development, fecundity, and locomotion. Our studies provide first evidence that human c-Met mutations can be studied in C. elegans, and that carcinogens can enhance mutant c-Met function expressed in C. elegans transgenic animals. We therefore propose the use of C. elegans as a model to rapidly assess the role of cancer specific gene mutations in the context of a whole organism.

Role of protein kinase C β and vascular endothelial growth factor receptor in malignant pleural mesothelioma: Therapeutic implications and the usefulness of Caenorhabditis elegans model organism

Purpose: To examine the role of both protein kinase C (PKC)-β and vascular endothelial growth factor receptor (VEGFR)-2 in malignant pleural mesothelioma (MPM) using respective inhibitors, enzastaurin and KRN633. Materials and Methods: MPM cell lines, control cells, and a variety of archived MPM tumor samples were used to determine the protein expression levels of PKC-β, VEGFR-2, VEGF, and p-AKT. Effects of enzastaurin and KRN633 on phosphorylation status of key signaling molecules and viability of the mesothelioma cells were determined. The common soil nematode, Caenorhabditis elegans, was treated with enzastaurin to determine its suitability to screen for highly potent kinase inhibitors. Results: PKC-β1, PKC-β2 and VEGFR-2/KDR were overexpressed in MPM cell lines and MPM tumor tissues. Enzastaurin treatment resulted in significant loss in viability of VEGF induced cell proliferation; however, the effect of KRN633 was much less. Enzastaurin also dramatically decreased the phosphorylation of PKC-β, its downstream target p-AKT, and surprisingly, the upstream VEGFR-2. The combination of the two drugs at best was additive and similar results were obtained with respect to cell viability. Treatment of C. elegans with enzastaurin resulted in clear phenotypic changes and the worms were hypermotile with abnormal pattern and shape of eggs, suggesting altered fecundity. Conclusions: PKC-β1 and VEGFR-2 are both excellent therapeutic targets in MPM. Enzastaurin was better at killing MPM cells than KRN633 and the combination lacked synergy. In addition, we show here that C. elegans can be used to screen for the next generation inhibitors as treatment with enzastaurin resulted in clear phenotypic changes that could be assayed.

Partner in fat metabolism: role of KLFs in fat burning and reproductive behavior.

The abnormalities caused by excess fat accumulation can result in pathological conditions which are linked to several interrelated diseases, such as cardiovascular disease and obesity. This set of conditions, known as metabolic syndrome, is a global pandemic of enormous medical, economic, and social concern affecting a significant portion of the world’s population. Although genetics, physiology and environmental components play a major role in the onset of disease caused by excessive fat accumulation, little is known about how or to what extent each of these factors contributes to it. The worm, Caenorhabditis elegans offers an opportunity to study disease related to metabolic disorder in a developmental system that provides anatomical and genomic simplicity relative to the vertebrate animals and is an excellent eukaryotic genetic model which enable us to answer the questions concerning fat accumulation which remain unresolved. The stored triglycerides (TG) provide the primary source of energy during periods of food deficiency. In nature, lipid stored as TGs are hydrolyzed into fatty acids which are broken down through β-oxidation to yield acetyl-CoA. Our recent study suggests that a member of C. elegans Krüppel-like factor, klf-3 regulates lipid metabolism by promoting FA β-oxidation and in parallel may contribute in normal reproduction and fecundity. Genetic and epigenetic factors that influence this pathway may have considerable impact on fat related diseases in human. Increasing number of studies suggest the role of mammalian KLFs in adipogenesis. This functional conservation should guide our further effort to explore C. elegans as a legitimate model system for studying the role of KLFs in many pathway components of lipid metabolism.

Pharmacokinetics of glycopyrronium/formoterol fumarate dihydrate delivered via metered dose inhaler using co-suspension delivery technology in patients with moderate-to-very severe COPD

Purpose The efficacy and tolerability of GFF MDI (Bevespi Aerosphere®), a fixed-dose combination of glycopyrronium (GP)/formoterol fumarate dihydrate (FF) 14.4/10 μg (equivalent to glycopyrrolate/formoterol fumarate 18/9.6 μg) delivered by metered dose inhaler (MDI) using innovative co-suspension delivery technology, has been investigated in a Phase III clinical trial program (NCT01854645, NCT01854658, NCT01970878) in patients with COPD. Here, we present findings from a pharmacokinetic (PK) sub-study of NCT01854645 (PINNACLE-1). Methods PINNACLE-1 was a multicenter, randomized, double-blind, parallel-group, 24 wk chronic-dosing, placebo- and active-controlled study. The PK sub-study assessed the systemic accumulation of glycopyrronium and formoterol following administration of GFF MDI 14.4/10 μg, GP MDI 14.4 μg, or FF MDI 10 μg (all BID) for 12 wks. Plasma for PK analysis was collected for up to 12 h after dosing, on Day 1 and Week 12. Results Of 2,103 patients randomized in PINNACLE-1, 292 participated in the PK sub-study. The plasma concentration–time profiles of glycopyrronium were similar following treatment with GFF MDI or GP MDI, both after single dosing and at Week 12. Accumulation at Week 12 relative to Day 1 was up to 2.30-fold for glycopyrronium. The plasma concentration–time profiles of formoterol were similar following treatment with GFF MDI or FF MDI, both after single dosing and at Week 12. Accumulation at Week 12 relative to Day 1 was up to 1.62-fold for formoterol. Conclusion Overall, the results have characterized the accumulation of glycopyrronium and formoterol associated with GFF MDI, GP MDI, and FF MDI, and indicated that there were no meaningful PK interactions, whether drug–drug or due to formulation, between glycopyrronium and formoterol following treatment with GFF MDI formulated using co-suspension delivery technology.

Randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of three doses of co-suspension delivery technology glycopyrronium MDI in Japanese patients with moderate-to-severe COPD.

Purpose Due to the burden of COPD in Japan, new pharmacologic treatments are needed to meet patient requirements. This study assessed the efficacy and safety of glycopyrronium (GP) delivered via metered dose inhaler (MDI) in Japanese patients with moderate-to-severe COPD. Methods This Phase IIb, multicenter, randomized, double-blind, 7-day, crossover study compared GP MDI 28.8, 14.4, and 7.2 μg with placebo MDI (all administered as two inhalations, twice daily). The primary endpoint was change from baseline in morning pre-dose trough forced expiratory volume in 1 second (FEV1) on Day 8. Secondary endpoints included FEV1 area under the curve from 0 to 2 hours (AUC0–2) and peak change from baseline in FEV1 on Days 1 and 8 and forced vital capacity AUC0–2 on Day 8. Safety was also assessed. ClinicalTrials.gov Identifier: NCT03256552; http://www.ClinicalTrials.gov. Results Sixty-six patients were randomized and 62 were included in the modified intent-to-treat population (mean age 67.5 years). All three GP MDI doses significantly improved change from baseline in morning pre-dose trough FEV1 on Day 8 compared with placebo MDI (least squares mean differences 108–131 mL; all p<0.0001). Significant improvements in secondary efficacy endpoints were also observed for all three GP MDI doses compared with placebo MDI (all p<0.0001). Dose–response plateaued at GP MDI 14.4 μg. No significant safety findings were observed with any GP MDI dose or placebo MDI. Conclusions The results of this study suggest that GP MDI 14.4 μg (7.2 μg per inhalation) is the most appropriate dose for use in Phase III studies in Japanese patients with moderate-to-severe COPD.

Randomized study of the effects of Aerochamber Plus ® Flow-Vu ® on the efficacy, pharmacokinetics and safety of glycopyrronium/formoterol fumarate dihydrate metered dose inhaler in patients with chronic obstructive pulmonary disease

OBJECTIVES This study compared the efficacy, pharmacokinetics (PK), and safety of GFF MDI (Bevespi Aerosphere®), a fixed-dose combination of glycopyrronium and formoterol fumarate dihydrate (14.4/10 μg) delivered by a metered dose inhaler (MDI) formulated using innovative co-suspension delivery technology, in patients with moderate-to-very severe chronic obstructive pulmonary disease (COPD) with and without the Aerochamber Plus® Flow-Vu® valved holding chamber (VHC). METHODS In this multicenter, open-label, crossover, Phase III study (NCT02454959), patients were randomized to receive GFF MDI 14.4/10 μg (equivalent to glycopyrrolate/formoterol fumarate 18/9.6 μg) twice daily for 7 days with and without the VHC. The primary endpoint was forced expiratory volume in 1 s area under the curve from 0 to 12 h (FEV1 AUC0-12) on Day 8. Steady state PK parameters for glycopyrronium and formoterol (AUC0-12, peak concentration [Cmax] and time to peak concentration [tmax]) were estimated from 12-h plasma concentration time data on Day 8. Safety and tolerability were also assessed throughout. RESULTS Eighty patients were randomized. On Day 8, the ratio (90% confidence interval [CI]) of least squares mean (LSM) FEV1 AUC0-12 for GFF MDI with VHC (LSM = 1538 mL; n = 67) versus without VHC (LSM = 1516 mL; n = 68) was 101.4% (100.1, 102.7). PK parameters were comparable overall with a slightly higher exposure to glycopyrronium with the VHC. The AUC0-12 geometric LSM ratio (90% CI) for GFF MDI with versus without VHC was 115.99% (99.74, 134.89) for glycopyrronium and 96.66% (86.69, 107.78) for formoterol. GFF MDI with and without VHC were well tolerated with a similar adverse event profile. CONCLUSIONS The magnitude of bronchodilatory effect was similar with and without a VHC following GFF MDI treatment. This, together with the PK and safety profiles, supports the use of the VHC with GFF MDI for the maintenance treatment of COPD, which could be particularly useful for patients who have difficulty with the coordination of an MDI.

Safety and pharmacokinetics of budesonide/glycopyrronium/formoterol fumarate dihydrate metered dose inhaler (BGF MDI) in healthy adult subjects of Japanese descent

INTRODUCTION BGF MDI, a budesonide, glycopyrronium, and formoterol fumarate dihydrate triple fixed-dose combination metered dose inhaler formulated using co-suspension delivery technology, is currently in Phase III global development for chronic obstructive pulmonary disease. METHODS This was a Phase I, randomized, double-blind, placebo-controlled, ascending-dose, crossover study to assess the safety and pharmacokinetic profiles of two doses of BGF MDI in healthy adult subjects of Japanese descent (NCT02197975). Safety assessments included monitoring for adverse events (AEs). Pharmacokinetic parameters were assessed following a single dose and 7-days chronic dosing with BGF MDI 160/14.4/10 μg and BGF MDI 320/14.4/10 μg. RESULTS Twenty subjects were randomized and included in the safety and pharmacokinetic populations; mean age 29.7 years; 65% male; and mean body mass index of 21.9 kg/m2. The incidences of treatment-emergent AEs (TEAEs) were similar between treatments. All the TEAEs were mild to moderate in severity. Budesonide area under the plasma concentration-time curve from 0 to 12 h (AUC0-12) and maximum observed plasma concentration (Cmax) values were approximately double for the higher dose of BGF MDI compared with the lower dose on Day 1 and also following chronic dosing on Day 8. Glycopyrronium and formoterol AUC0-12 and Cmax values on Day 8 were comparable between the two doses of BGF MDI. DISCUSSION Both doses of BGF MDI were well tolerated in healthy subjects of Japanese descent and the systemic exposure to budesonide was dose proportional for BGF MDI 160/14.4/10 μg and BGF MDI 320/14.4/10 μg. The safety and pharmacokinetics for BGF MDI 160/14.4/10 μg and BGF MDI 320/14.4/10 μg in Japanese subjects were comparable to data from previous studies in Western populations, which suggests that the safety and efficacy profile of BGF MDI should be similar in Western and Japanese subjects.

Pharmacokinetics and safety of a single dose of the novel LAMA/LABA fixed-dose combination of glycopyrronium/formoterol fumarate dihydrate metered dose inhaler, formulated using co-suspension delivery technology, in Japanese healthy subjects

BACKGROUND Chronic obstructive pulmonary disease (COPD) causes significant mortality in Japan. GFF MDI is a long-acting muscarinic antagonist/long-acting β2-agonist fixed-dose combination of glycopyrronium (GP) and formoterol fumarate dihydrate (FF), delivered by a metered dose inhaler (MDI) using co-suspension delivery technology, for the long-term maintenance treatment of COPD. METHODS This randomized, Phase I, single-dose, four-treatment, four-period, crossover study (NCT02196714) examined the pharmacokinetic (PK) and safety profile of two doses of GFF MDI (28.8 μg/10 μg and 14.4 μg/10 μg) and two doses of GP MDI (28.8 μg and 14.4 μg), both formulated using co-suspension delivery technology, in healthy Japanese subjects (18-45 years of age). PK parameters included area under the curve (AUC) from 0 to 12 h (AUC0-12), AUC from 0 to the time of the last measurable plasma concentration, maximum observed plasma concentration (Cmax), and time to Cmax. Safety was monitored throughout the study. RESULTS Plasma GP profiles were comparable between GFF MDI and GP MDI formulations containing the same GP dose. Increases in GP AUC0-12 and Cmax were generally dose proportional from 14.4 to 28.8 μg after administration of either formulation. CONCLUSIONS The addition of FF 10 μg to GP MDI 28.8 μg or 14.4 μg in a fixed-dose combination did not appreciably alter the PK of GP, nor did an increase in GP dose from 14.4 μg to 28.8 μg in a fixed-dose combination with FF 10 μg appreciably alter the PK of formoterol. Both formulations of GFF MDI and GP MDI were well tolerated in healthy Japanese subjects. Data from this study support further evaluation of GFF MDI in Japanese patients with COPD.

A randomized study using functional respiratory imaging to characterize bronchodilator effects of glycopyrrolate/formoterol fumarate delivered by a metered dose inhaler using co-suspension delivery technology in patients with COPD

Background Functional respiratory imaging (FRI) uses high-resolution computed tomography (HRCT) scans to assess changes in airway volume and resistance. Patients and methods In this randomized, double-blind, 2-week, crossover, Phase IIIB study, patients with moderate-to-severe COPD received twice-daily glycopyrrolate/formoterol fumarate delivered by a metered dose inhaler (GFF MDI, 18/9.6 μg) and placebo MDI, formulated using innovative co-suspension delivery technology. Co-primary endpoints included the following: specific image-based airway volume (siVaw) and specific image-based airway resistance (siRaw) at Day 15, measured using FRI. Secondary and other endpoints included the following: change from baseline in post-dose forced expiratory volume in 1 second (FEV1) and inspiratory capacity (IC; spirometry) and ratio to baseline in post-dose functional residual capacity (FRC) and residual volume (RV; body plethysmography). Results Twenty patients (46–78 years of age) were randomized and treated; of whom 19 completed the study. GFF MDI treatment increased siVaw by 75% and reduced siRaw by 71% vs placebo MDI (both P<0.0001). Image-based airway volume (iVaw) and image-based airway resistance (iRaw), without adjusting for lobe volume, demonstrated corresponding findings to the co-primary endpoint, as lobe volumes did not change with either treatment. Approximately 48% of the delivered dose of glycopyrronium and formoterol fumarate was estimated to be deposited in the lungs. Compared with placebo, GFF MDI treatment improved post-dose FEV1 and IC (443 mL and 454 mL, respectively; both P<0.001) and reduced FRC and RV (13% and 22%, respectively; both P<0.0001). There were no significant safety findings. Conclusion GFF MDI demonstrated significant, clinically meaningful benefits on FRI-based airway volume and resistance in patients with moderate-to-severe COPD. Benefits were associated with improvements in FEV1, IC, and hyperinflation. Clinical trial registration ClinicalTrials.gov: NCT02643082.