Defective lipid metabolism associated with mutation in klf-2 and klf-3: important roles of essential dietary salts in fat storage

Background

Dietary salts are important factors in metabolic disorders. They are vital components of enzymes, vitamins, hormones, and signal transduction that act synergistically to regulate lipid metabolism. Our previous studies have identified that Krüppel-like factor −3 (KLF-3) is an essential regulator of lipid metabolism. However, it is not known if KLF-2 also regulates lipid metabolism and whether KLF-2 and −3 mediate the effects of dietary salts on lipid metabolism.

Methods

In this study, we used klf mutants [homozygous klf-2 (ok1043) V and klf-3 (ok1975) II mutants] to investigate the role of dietary salts in lipid metabolism. All gene expression was quantified by qRT-PCR. Localization of KLF-2 was analyzed by the expression of klf-2::gfp (in pPD95.75 vector) using a fluorescent microscope. Fat storage was measured by Oil Red O staining.

Results

Klf-2 was identified to express in the intestine during all stages of Caenorhabditis elegans development with peak expression at L3 stage. Mutation of klf-2 increased fat accumulation. Under regular growth media free of Ca^2+, the expression of both klf-2 and −3 was inhibited slightly; further their expression reduced significantly in WT worms fed on 10X Ca²⁺ diet. When klf-3 was mutated, the expression of klf-2 increased under 10X Ca²⁺ diet; but when klf-2 was mutated, the expression of klf-3 was not altered under 10X Ca²⁺ diet. Overall, Mg²⁺ and K⁺ were less effective on the gene expression of klfs. KLF target gene Ce-C/EBP-2 showed elevated expression in WT and klf-3 (ok1975) worms with changed Ca²⁺ concentrations but not in klf-2 (ok1043) worms. However, high Ca⁺² diet exhibited inhibitory effect on Ce-SREBP expression in WT worms.

Conclusion

Dietary Ca²⁺ is most effective on fat storage and klf-2 expression, wherein high Ca²⁺ diet decreased klf-2 expression and reduced fat buildup. Mechanistic study identified Ce-C/EBP (C48E7.3; lpd-2) and Ce-SREBP (Y47D3B.7; lpd-1) as the target genes of klf-2 and/or klf-3 to mediate lipid metabolism. This study identifies a new function of klf-2 in inhibiting fat buildup and reveals the interplay between dietary salts and klf-2 and klf-3 in lipid metabolism.

Dronabinol increases pain threshold in patients with functional chest pain: a pilot double-blind placebo-controlled trial

Noncardiac chest pain is associated with poor quality of life and high care expenditure. The majority of noncardiac chest pain is either gastresophageal reflux disease related or due to esophageal motility disorders, and the rest are considered functional chest pain (FCP) due to central and peripheral hypersensitivity. Current treatment of FCP improves 40-50% of patients. Cannabinoid receptors 1 (CB1) and 2 (CB2) modulate release of neurotransmitters; CB1 is located in the esophageal epithelium and reduces excitatory enteric transmission and potentially could reduce esophageal hypersensitivity. We performed a prospective study to evaluate its effects on pain threshold, frequency, and intensity in FCP. Subjects with FCP received dronabinol (5 mg, twice daily; n = 7; average age, 44 years; mean body mass index, 26.7) or placebo (n = 6; average age, 42 years; mean body mass index, 25.9) for 28 days (4 weeks). Chest pain, general health, and anxiety/depression questionnaires were assessed at baseline and at 4 weeks. Subjects underwent an esophageal balloon distention test prior to treatment and on last day of the study. Dronabinol increased pain thresholds significantly (3.0 vs. 1.0; P = 0.03) and reduced pain intensity and odynophagia compared to placebo (0.18 vs. 0.01 and 0.12 vs. 0.01, respectively, P = 0.04). Depression and anxiety scores did not differ between the groups at baseline or after treatment. No significant adverse effects were observed. In this novel study, dronabinol increased pain threshold and reduced frequency and intensity of pain in FCP. Further, large scale studies are needed to substantiate these findings.

Corticosteroid use as adjunct therapy for respiratory syncytial virus infection in adult allogeneic stem cell transplant recipients

BACKGROUND

Respiratory syncytial virus (RSV) infection causes significant morbidity and mortality in allogeneic stem cell transplant (allo-SCT) recipients. Although ribavirin and immunoglobulins are common components of therapy, the role of adjunct corticosteroids is not established.

OBJECTIVES

We sought to evaluate corticosteroid utilization in the setting of post-allo-SCT RSV infection in our center and assess post-transplant outcomes including pulmonary function decline.

METHODS

Patients with a history of RSV infection from 2008 to 2014 seen at our institution were identified. Treatment and outcome data were retrospectively collected. Forced expiratory volume at 1 s (FEV1) and carbon monoxide diffusion capacity (DLCO) were collected pre- and post-RSV infection.

RESULTS

During the observation period, RSV was isolated in 53 of 552 patients undergoing allo-SCT (10%) and 45 had evaluable therapy data. RSV-related mortality in this cohort was 4/45 (9%). Twenty-one (47%) were on corticosteroids prior to RSV diagnosis, of whom 11 (24%) had a dose increase post symptom onset. Eight (18%) patients were started on corticosteroids at the time of RSV infection. Corticosteroid therapy at symptom onset was associated with a higher rate of upper respiratory infection (URTI) to lower respiratory infection (LRTI) progression risk ratio (RR) 2.49 (1.21-5.13; P = 0.016), hospital admission RR 2.05 (1.24-3.37; P = 0.005), or intensive care unit admission RR 2.91 (1.89-5.01; P = 0.002). No significant difference was seen with FEV1 and DLCO decline (P = 0.3 and 0.24, respectively) or mortality (P = 0.26).

CONCLUSION

Adjunct corticosteroid use in the setting of RSV infection did not improve RSV-related outcomes including long-term pulmonary function. Our results do not support the routine use of corticosteroids; however, this finding does need to be verified in a larger cohort of patients.

Tuberculosis--frequency and differential diagnosis--analysis of cases in Pakistan

BACKGROUND

Tuberculosis is highly prevalent in Pakistan and the numbers are on increase each year. Cervical lymphadenopathy, a common finding in tuberculosis and other inflammatory, infectious and malignant etiologies, is commonly encountered in hospital setting in Karachi, Pakistan. Signs and symptoms of tuberculosis are blood tinged sputum, weight loss, night sweats, loss of appetite and weakness. A through history, complete physical examination and investigations are needed to diagnose tuberculosis.

OBJECTIVE

To determine the burden of tuberculosis in cases of cervical lymphadenopathy and to find the most common etiologies of cervical lymphadenopathy in hospital setup in Karachi, Pakistan.

METHODS AND MATERIALS

Patients with cervical lymphadenopathy attending the surgical outpatient department of Jinnah Post Graduate Center, Karachi, Pakistan were conveniently sampled for this study without age and gender limitations. This cross sectional, descriptive study was conducted from January 2010 to January 2011.

RESULTS

A total of 250 patient cases with cervical lymphadenopathy were studied. The age group with the highest number of patients was between 21 to 40 years, which included 97 females and 21 males. The patients with unilateral single cervical lymph node swelling were found to be 13.2%, while 86.8 % patients had multiple bilateral lymph node swellings. Tuberculosis was found in majority of patients, 63.6% followed by inflammatory hyperplasia which was present in 28.4% patients, other causes included lymphoma 5.2% and metastasis 2.8%.

CONCLUSION

Tuberculosis is the most common etiology of cervical lymphadenopathy, followed by inflammatory hyperplasia, lymphoma and metastasis.

Abstract PD5-6: Sustained hyperactivated mTOR & JAK2/STAT3 pathways in inflammatory breast cancer (IBC): Evidence for mTOR plus JAK2 therapeutic targeting

Background: IBC is an aggressive form of breast cancer with poor prognosis. Combined multi-modality therapy results in a 5 year OS of 30%, underscoring the unmet need for targeted therapy. Our preclinical research in cell lines & xenograft tumor models has identified a role for hyper-activated PI3K/mTOR signaling in IBC. IBC cells express IL-6 and IL-8, which recruit tumor activated macrophages (TAMs) that further induce inflammatory cytokines and activate the JAK2/STAT3 pathway. We investigated the independent and combined activity of these pathways in IBC patient tissues.

Methods: Archived tissue specimens of 42 IBC patients (dx 1999-2009) and 27 non-IBC patients (dx 2001-2005) with invasive ductal carcinoma (IDC) were obtained. Surrounding non-tumor normal tissue from IBC (companion controls) was also utilized. All specimens were analyzed using immunohistochemistry (IHC) and scored by 3 independent pathologists. Results were defined as 0 = negative; 1+,2+ = positive for activated mTOR (P-S6); activated JAK2/STAT3 (P-JAK2; P-STAT3); cytokine (IL-6); macrophage infiltration (CD68) and TAM (CD163). Proportions of IBC cases with positive expression were compared with non-IBC cases (Fisher's exact test) & companion controls (McNemar's test). Clinical & survival data were obtained.

Results: Median age at diagnosis: 46 yrs (31-62) in early stage IBC [EIBC] (n = 37) & 41 yrs (29-57) in pts with de novo metastatic IBC [MIBC] (n = 5). In EIBC, 19/36: HER2+ (1 unk); 8/19: ER+/HER2+; 8/36: ER-/HER2-. In MIBC, all were ER- (1 unk) & 3/4 were HER2+ (1 unk). 88% were rx with neoadjuvant &/or adjuvant anthracycline & taxane w/o adjuvant trastuzumab. There were 24 pt deaths (5/5 MIBC). Median f/u for EIBC: 6.3 yrs and for MIBC: 3.4 yrs. Median OS: 81.4 mo (95% CI lower 48 mo) for EIBC & 41 mo (95% CI 8-81 mo) for MIBC. Median RFS: 18 mo (95% CI 18-79 mo) for 23 pts (13 NED; 1 unk). The non-IBC patients were all stage 2-3 with median age at diagnosis: 58 yrs (39-94). 19/27: ER+; 7/25 HER2+ (2 unk); 15/25 ER+/HER2-; 3/25 ER-/HER2-. 78% were rx with adjuvant anthracycline & taxane, 4% were rx with FEC and 18% did not receive adjuvant chemotherapy. 18% received adjuvant trastuzumab. Median f/u: 8.0 yrs. Median OS: not yet reached and median RFS: 111.3 mo (95% CI lower 34.5 mo). EIBC cases were compared with non-IBC cases & companion controls (Table 1). PS6, pJAK2 and pSTAT3 expression was significantly increased in IBC compared to non-IBC. Of the 29 EIBC patients with complete biomarker data who were PS6+, 28/29 (97%) were JAK2+, 15/29 (52%) were STAT3+, 26/29 (90%) were CD68+, 20/29 (69%) were CD163+ and 28/29 (97%) were IL6+.

Conclusion: This is the first study to validate preclinical findings & show a strong co-association between hyper-activation of mTOR & JAK/STAT pathways in most IBC patient tumors when compared to surrounding non-tumor tissue and non-IBC (IDC) tumors and tissues. These findings suggest a key role for dual blockade of mTOR & JAK/STAT pathways for IBC in phase I trials.

BiomarkerMcNemars p-value: Early Stage IBC vs companion controls (N = 37)Fishers p-value: Early stage IBC (N = 37)vs non-IBC (N = 27)PS6<0.00010.0315pJAK2<0.0001<0.0001pSTAT30.0003<0.0001CD163<0.00010.0908CD68<0.00010.0582IL60.00030.3882

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD5-6.

Abstract P5-13-06: Seasonal variation in onset of inflammatory breast cancer: Evidence of an infectious trigger

Introduction:

Inflammatory breast cancer (IBC) is a rare but extraordinarily aggressive disease with a number of studies indicating that environmental factors play the most important role. We have identified four reported clusters of IBC and our investigations thus far suggest that local toxic or infectious agents could be involved in the pathogenesis of the disease. IBC, like Burkitt's lymphoma (BL) has been reported to cluster and both have been implicated with infectious agents. Since BL has been reported to have a seasonal variation attributed to acute malaria symptoms as the precipitating agent, we decided to investigate the seasonality of IBC in two populations.

Methods:

For our analysis we used the datasets of two IBC referral groups. The first group consisted of a series of 163 consecutive cases of patients seen at Fox Chase Cancer Center (FCCC) almost all being from the Northeast U.S. (NE) and Canada. At the time of initial visit a detailed series of questions was specifically directed at identifying the accurate time of the first onset of symptoms/signs including skin rash, swelling, pain, nipple retraction and palpable mass. The second was the IBC registry (IBCR), established at the George Washington University with the purpose of collecting standardized clinical and epidemiologic data (including a detailed interview) and biospecimens from patients with IBC in the U.S and Canada. Complete data on patients in both groups were evaluated, including diagnostic workup, pathologic findings and treatment.

Results:

Of the 163 FCCC patients, 156 had the month of onset of symptoms clearly delineated. Of the 161 patients in the IBCR, 153 had month of symptomatic onset defined. In the combined groups, 181 NE patients were compared with 63 from the South. A seasonal pattern was noted in the NE patients, a bimodal pattern showing most patients with onset in March and July-Sept. No seasonal pattern was noted in patients from the South.

Conclusion:

The reports of IBC clusters are consistent with an acute triggering factor, possibly an infection. The seasonality we observed in NE patients but not in southern patients is consistent with this hypothesis. We are currently continuing to investigate clusters of IBC and are testing for specific candidate infectious agents as well as candidate environmental toxic agents to further understand possible triggers for this disease.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-06.

Pediatric kidney transplantation in the developing world: challenges and solutions

The prevalence of pediatric RRT and transplantation are low in developing countries, 6-12 and <1 to 5 per million child population (pmcp), respectively. This is due to low GDP/capita of <$10 000, government expenditure on health of <2.6-9% of GDP and paucity of facilities. The reported incidence of pediatric CKD and ESRD is <1.0-8 and 3.4-35 pmcp, respectively. RRT and transplantation are offered mostly in private centers in cities where HD costs $20-100/session and transplants $10 000-20 000. High costs and long distance to centers results in treatment refusal in up to 35% of the cases. In this backdrop 75-85% of children with ESRD are disfranchised from RRT and transplantation. Our center initiated an integrated dialysis-transplant program funded by a community-government partnership where RRT and transplantation was provided "free of cost" with life long follow-up and medication. Access to free RRT at doorsteps and transplantation lead to societal acceptance of transplantation as the therapy of choice for ESRD. This enabled us to perform 475 pediatric transplants in 25 years with 1- and 5-year graft survival of 96% and 81%, respectively. Our model shows that pediatric transplantation is possible in developing countries when freely available and accessible to all who need it in the public sector.

Regulation of lipoprotein assembly, secretion and fatty acid β-oxidation by Krüppel-like transcription factor, klf-3

Lipid metabolism is coordinately regulated through signaling networks that integrate biochemical pathways of fat assimilation, mobilization and utilization. Excessive diversion of fat for storage is a key risk factor for many fat-related human diseases. Dietary lipids are absorbed from the intestines and transported to various organs and tissues to provide energy and maintain lipid homeostasis. In humans, disparity between triglycerides (TG) synthesis and removal, via mitochondrial β-oxidation and VLDL (very low density lipoprotein) secretion, causes excessive TG accumulation in the liver. The mutation in Caenorhabditis elegans KLF-3 leads to high TG accumulation in the worm's intestine. Our previous data suggested that klf-3 regulates lipid metabolism by promoting fatty acid β-oxidation. Depletion of cholesterol in the diet has no effect on fat deposition in klf-3 (ok1975) mutants. Addition of vitamin D in the diet, however, increases fat levels in klf-3 worms. This suggests that excess vitamin D may be lowering the rate of fatty acid β-oxidation, with the eventual increase in fat accumulation. We also demonstrate that mutation in klf-3 reduces expression of C. elegans dsc-4 and/or vit genes, the orthologs of mammalian microsomal triglyceride transfer protein and apolipoprotein B, respectively. Both microsomal triglyceride transfer protein and apolipoprotein B are essential for mammalian lipoprotein assembly and transport, and mutation in both dsc-4 (qm182) and vit-5 (ok3239) results in high fat accumulation in worm intestine. Genetic interactions between klf-3 and dsc-4, as well as vit-5 genes, suggest that klf-3 may have an important role in regulating lipid assembly and secretion.

A C. elegans model to study human metabolic regulation

Lipid metabolic disorder is a critical risk factor for metabolic syndrome, triggering debilitating diseases like obesity and diabetes. Both obesity and diabetes are the epicenter of important medical issues, representing a major international public health threat. Accumulation of fat in adipose tissue, muscles and liver and/or the defects in their ability to metabolize fatty acids, results in insulin resistance. This triggers an early pathogenesis of type 2 diabetes (T2D). In mammals, lipid metabolism involves several organs, including the brain, adipose tissue, muscles, liver, and gut. These organs are part of complex homeostatic system and communicate through hormones, neurons and metabolites. Our study dissects the importance of mammalian Krüppel-like factors in over all energy homeostasis. Factors controlling energy metabolism are conserved between mammals and Caenorhabditis elegans providing a new and powerful strategy to delineate the molecular pathways that lead to metabolic disorder. The C. elegans intestine is our model system where genetics, molecular biology, and cell biology are used to identify and understand genes required in fat metabolism. Thus far, we have found an important role of C. elegans KLF in FA biosynthesis, mitochondrial proliferation, lipid secretion, and β-oxidation. The mechanism by which KLF controls these events in lipid metabolism is unknown. We have recently observed that C. elegans KLF-3 selectively acts on insulin components to regulate insulin pathway activity. There are many factors that control energy homeostasis and defects in this control system are implicated in the pathogenesis of human obesity and diabetes. In this review we are discussing a role of KLF in human metabolic regulation.

Frequency and type of toenail tumors in the dromedary camel

A total of 275 dromedary camels (16 males and 259 females) of local "Arabiyat" breed suffering from different types and degrees of severity of toenail tumors were surgically treated. Histopathological examination of the tissue samples removed from 50 tumor-like growths (2 males and 48 females) revealed three types of tumors; squamous cell carcinoma (70%), spiny keratoderma (22%) and fibroma (8%). An increased incidence of tumors was recorded in the medial when compared to the lateral toenails in both sexes. In females, the incidence in the medial toenails was 90/259 (34.75%) and 71/259 (27.41%) in the right and left forelimbs respectively when compared to the lateral toenails which was 25/259 (9.65%) and 5/259 (1.93%) for the respective right and left forelimbs. In the hind limbs, this ratio was 29/259 (11.20%) and 20/259 (7.72%) for right and left medial toenails respectively, whereas it was 17/259 (6.56%) and 2/259 (0.77%) for the right and left lateral toenails respectively. Similar to the observations in female camels, male camels also showed a higher incidence of these tumors in the medial when compared to the lateral toenails in both fore and hind limbs. Based on these findings, we conclude that in the dromedary camels, the medial toenails of the fore limbs are most commonly affected with tumors; with the most common tumor being the squamous cell carcinoma.

Fixation of metatarsal fracture with bone plate in a dromedary heifer

An oblique fracture of the distal third of the right metatarsus in a three-year-old dromedary heifer weighing about 300 kilograms was immobilized with a 4.5 mm broad-webbed 12-hole dynamic compression bone plate and two interfragmental compression screws. The animal showed slight lameness after 16 weeks of surgery that disappeared after removal of the plate. The result was quite encouraging and the fracture healed in 16 weeks without major complications. It is concluded that the fracture of this bone can be successfully handled with bone plating at least in young, light weight animals.

P2-05-09: Secondary Inflammatory Breast Cancer: A Possible Model for Post-Surgical Dissemination of Cancer

Background: The phenomenon of accelerated tumor growth following surgery has been observed repeatedly and merits further study. Inflammatory breast carcinoma (IBC) is widely recognized as an extremely aggressive malignancy characterized by micrometastasis at the time of diagnosis. It is fast growing, highly angiogenic and angioinvasive, features that are present from its inception. The idea of a dormant cancer cell and awakening of metastatic disease following a surgical/traumatic event may well be exemplified by secondary IBC, a term used to describe the IBC appearing following surgery for a noninflammatory primary breast carcinoma. One possible mechanism can be related to the stimulation of dormant micrometastasis through local angiogenesis occurring as part of posttraumatic healing. It is therefore possible that secondary IBC can be used as a model to support local angiogenesis as an important contributor to the development of an aggressive cancer.

Materials and Methods: Cases of secondary IBC were identified in a review of patients referred to the IBC Registry (IBCR). In this report we document the histories of three patients with secondary IBC as well as two additional patients whose disease presentation also supports the possible occurrence of IBC secondary to breast trauma. Secondary IBC cases were defined as women who had surgery for non-inflammatory breast cancer with recurrence at the previous mastectomy site manifest as skin erythema shown to be associated with pathologically confirmed tumor emboli in the dermal lymphatics.

Results: Two of the patients with secondary IBC developed pathologically confirmed dermal lymphatic invasion two and 42 months after partial mastectomy for non-inflammatory breast cancer. The third had been apparently free of recurrence for seven years when she had reconstructive surgery, which was followed by IBC seven months later. Two additional cases are presented, one in which IBC manifested one month following ductogram procedure and had a contralateral breast IBC recurrence 2 years later. The other patient was diagnosed with IBC one year following nipple piercing and ring removal.

Discussion: Recent publications have focused on the role of surgery in the subsequent development of metastatic breast cancer, many of them focusing on a hormonal mechanism triggered by removal of the primary tumor. We propose local angiogenesis as another possible mechanism for post-surgical dissemination of cancer. In view of the hypothesis that trauma can stimulate angiogenesis which can accelerate tumor growth, the documentation of IBC appearing at the site of a traumatic event merits consideration. Our experience with IBC, noted in the case reports above suggest that local trauma probably mediated in large part by angiogenesis can be an important trigger of IBC. We would therefore suggest that secondary IBC be considered for investigation of one possible mechanism for post-surgical tumor dissemination.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-05-09.

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.

Regulation of fat storage and reproduction by Krüppel-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.

An FTO variant is associated with Type 2 diabetes in South Asian populations after accounting for body mass index and waist circumference

AIMS

A common variant, rs9939609, in the FTO (fat mass and obesity) gene is associated with adiposity in Europeans, explaining its relationship with diabetes. However, data are inconsistent in South Asians. Our aim was to investigate the association of the FTO rs9939609 variant with obesity, obesity-related traits and Type 2 diabetes in South Asian individuals, and to use meta-analyses to attempt to clarify to what extent BMI influences the association of FTO variants with diabetes in South Asians.

METHODS

We analysed rs9939609 in two studies of Pakistani individuals: 1666 adults aged ≥40 years from the Karachi population-based Control of Blood Pressure and Risk Attenuation (COBRA) study and 2745 individuals of Punjabi ancestry who were part of a Type 2 diabetes case-control study (UK Asian Diabetes Study/Diabetes Genetics in Pakistan; UKADS/DGP). The main outcomes were BMI, waist circumference and diabetes. Regression analyses were performed to determine associations between FTO alleles and outcomes. Summary estimates were combined in a meta-analysis of 8091 South Asian individuals (3919 patients with Type 2 diabetes and 4172 control subjects), including those from two previous studies.

RESULTS

In the 4411 Pakistani individuals from this study, the age-, sex- and diabetes-adjusted association of FTO variant rs9939609 with BMI was 0.45 (95%CI 0.24-0.67) kg/m(2) per A-allele (P=3.0 × 10(-5) ) and with waist circumference was 0.88 (95% CI 0.36-1.41) cm per A-allele (P=0.001). The A-allele (30% frequency) was also significantly associated with Type 2 diabetes [per A-allele odds ratio (95%CI) 1.18 (1.07-1.30); P=0.0009]. A meta-analysis of four South Asian studies with 8091 subjects showed that the FTO A-allele predisposes to Type 2 diabetes [1.22 (95%CI 1.14-1.31); P=1.07 × 10(-8) ] even after adjusting for BMI [1.18 (95%CI 1.10-1.27); P=1.02 × 10(-5) ] or waist circumference [1.18 (95%CI 1.10-1.27); P=3.97 × 10(-5) ].

CONCLUSIONS

The strong association between FTO genotype and BMI and waist circumference in South Asians is similar to that observed in Europeans. In contrast, the strong association of FTO genotype with diabetes is only partly accounted for by BMI.

Investigation of esophageal sensation and biomechanical properties in functional chest pain

BACKGROUND

There is limited and conflicting data regarding the role of esophageal hypersensitivity in the pathogenesis of functional chest pain (FCP). We examined esophageal sensori-motor properties, mechanics, and symptoms in subjects with FCP.

METHODS

Esophageal balloon distension test was performed using impedance planimetry in 189 (m/f = 57/132) consecutive subjects with non-cardiac, non-reflux chest pain, and 36 (m/f = 16/20) healthy controls. The biomechanical and sensory properties of subjects with and without esophageal hypersensitivity were compared with controls. The frequency, intensity, and duration of chest pain were assessed.

KEY RESULTS

One hundred and forty-three (75%) subjects had esophageal hypersensitivity and 46 (25%) had normal sensitivity. Typical chest pain was reproduced in 105/143 (74%) subjects. Subjects with hypersensitivity demonstrated larger cross-sectional area (P < 0.001), decreased esophageal wall strain (P < 0.001) and distensibility (P < 0.001), and lower thresholds for perception (P < 0.01), discomfort (P < 0.01), and pain (P < 0.01) compared to those without hypersensitivity or healthy controls. Chest pain scores (mean +/- SD) for frequency, intensity and duration were 2.5 +/- 0.3, 2.2 +/- 0.2, and 2.2 +/- 0.2, respectively, and were similar between the two patient groups.

CONCLUSIONS & INFERENCES

Seventy-five per cent of subjects with FCP demonstrate esophageal hypersensitivity. Visceral hyperalgesia and sensori-motor dysfunction of the esophagus play a key role in the pathogenesis of chest pain.

Pain prevalence in patients with chronic kidney disease

BACKGROUND

The prevalence of pain in patients with chronic kidney diseases (CKD) is not known. In the current study, we aim to determine the prevalence of pain in CKD patients and its associations with various medical and psychosocial factors.

METHODS

Consecutive CKD patients who were presented to the renal clinic at Olive View-UCLA Medical Center, a Los Angeles County tertiary referral center, over a 3-month period were interviewed on their medical and psychosocial histories and a history of pain including duration, severity and source. Chi2-testing for independence and binary logistic regression performed for the presence of pain and CKD stages as well as other medical and psychosocial factors were determined. A separate survey for pain was also done for 100 consecutive non-CKD patients who were presented to our ambulatory medicine clinic for routine care.

RESULTS

54.6% of 130 patients with known CKD interviewed were women. Any type of pain of at least a 2 week duration was reported in 72.9%. The most common source of pain was musculoskeletal. The presence of pain of less than a 2 week duration was associated with worse CKD stages (3 - 5 versus 1 - 2) and non-exercisers. Higher body mass index was associated with having pain lasting longer than a 2 week duration. Among patients who had pain, 33.8% used acetaminophen, 15.4% nonsteroidal anti-inflammatory drugs and 7.8% combination analgesics. In contrast to CKD patients, only 9% of non-CKD patients reported to have any type or duration of pain.

CONCLUSIONS

Pain was much more prevalent among our CKD compared with non-CKD patients.