Retinol Binding Protien-4 Levels in Early Diabetic Nephropathy in Egyptian Patients with Type 2 Diabetes

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1 Glol Journl of Biotechnology & Biochemistry 10 (1): 39-46, 015 ISSN X IDOSI Pulictions, 015 DOI: /idosi.gj Retinol Binding Protien-4 Levels in Erly Dietic Nephropthy in Egyptin Ptients with Type Dietes Hmed M.H. Khlil, Ahmed E.S. Adll, Shrif M. Shrif nd Irhim W. Hsni 1 Biochemistry Deprtment, Fculty of Science, Ciro University, Egypt Clinicl nd Chemicl Pthology Deprtment, Fculty of Medicine, Ciro University, Egypt 3 Orgnic Chemistry Deprtment, Fculty of Science, Ciro University, Egypt Astrct: Plsm retinol-inding protein 4 (RBP4) is new dipokine linked to oesity-induced insulin resistnce nd type dietes. The impct of dietic nephropthy on serum RBP4 levels, however, is not well known. This study imed to investigte the reltionships etween serum levels of RBP4 nd vrious metolic prmeters in Egyptin ptients with TDM. Additionlly, the present study tested the hypothesis tht microluminuri is ssocited with elevted serum concentrtions of RBP4 in type dietic sujects. In cse control study, totl numer of 60 type dietic ptients nd 0 helthy sujects were enrolled in the present study. The prticipnts were mtched y ge nd sex. Dietic ptients were clssified into normoluminuri nd microluminuri sugroups ccording to the microlumin level in urine. Serum RBP4 nd micolumin were mesured y n enzyme-linked immunosorent ssy (ELISA).The results demonstrted sttisticlly significnt elevtion in serum RBP4 concentrtions in TDM sujects compred to control sujects, lso serum RBP-4 levels in mles were significntly higher in TDM ptients compred with mle control group, s well s in femles TDM ptients compred with femle control group. In TDM ptients, serum concentrtion of RBP4 ws positively correlted with ge, fsting lood sugr, post prndil lood sugr nd HA1c nd inversely correlted with femle gender. There were no significnt correltions etween RBP4 nd BMI, GFR, cholesterol, triglyceride, HDL, LDL, ure, cretinine, cretinine clernce nd uric cid. The serum RBP4 levels in micromcroluminuric ptients were significntly higher thn in normoluminuric ptients nd the control sujects. It could e concluded tht serum RBP4 levels were found to e elevted in sujects with TDM nd to e relted to vrious clinicl prmeters known to e ssocited with TDM, so levels of serum RBP4 might ply importnt role in the pthogenesis of TDM. Also, the present study suggests tht serum RBP4 levels in type dietic ptients re ffected y incipient nephropthy. Key words: Type dietes mellitus Retinol ending protein-4 Microluminuri INTRODUCTION circultes in complex with TTR, which mintins the serum RBP4 levels y preventing loss of the smller RBP4 is lypoclin protein trnsporting retinol in the protein (1 kd) from the circultion y filtrtion in the circultion. It is produced in the liver nd lso in mture renl glomeruli [4]. The receptors STRA6 on the surfce lipid-lden dipocytes [1, ]. In the smll intestine, vitmin of the trget cells ind to complex with high ffinity nd A (retinol) is sored, stored in liver nd secreted into medites vitmin A uptke into cells [5]. After delivery of circultion ound to serum retinol inding protein (RBP4). vitmin A to the trget cells, the RBP molecule loses its Circulting retinol my e tken up y extrheptic tissues ffinity for TTR. The smll RBP molecule (po-rbp) is or recycled ck to liver multiple times efore it is finlly filtered through the glomeruli nd is susequently metolized or degrded [3]. Following the secretion of resored nd degrded y the proximl tuulr cells [6]. retinol-rbp (holo-rbp4), RBP forms complexes with The regultion of RBP-4 is uncler, however RBPR ws nother plsm protein, trnsthyretin (TTR). RBP4 recently identified s high ffinity RBP4 receptor Corresponding Author: Hmed M.H. Khlil, Clinicl nd Chemicl Pthology Deprtment, Fculty of Medicine, Ciro University, Egypt. 39

2 Glol J. Biotech. & Biochem., 10 (1): 39-46, 015 expressed primrily in liver nd smll intestine nd fter 14 h overnight fst. Smll portion of ech lood induced in dipocytes of oese mice [7]. Mny studies smple ws collected in KEDTA for or determintion of showed tht RBP4 is decresed with hypocloric diet [8] glycosylted hemogloin. Another liquot ws collected s well s weight loss chieved y lifestyle [9] or weight s whole lood in sodium fluoride for plsm seprtion loss chieved y Singpore ritric surgery [10, 11]. The to e used for the immedite ssy of glucose. A third importnce role of RBP4 in the vitmin A metolism is liquot ws llowed to clot. The seprted serum ws reflected in the homeosttic regultion of plsm retinol used for the immedite ssy of ure, cretinine, uric cid (vitmin A), which gurntees supply constnt nd nd lipid profile y hitchi 911 (Kits supplied from Roch, continuous mount of vitmin A to peripherl tissues. USA). The lst liquot ws llowed to clot nd stored t Severl pthophysiologicl conditions might e the cuse -0 C for susequent estimtion of RBP4 y ELISA of sustntil fluctutions of plsm RBP4. Reduced (Anov, USA) [15]. Twenty four hour urine smples levels of plsm RBP4 ws due to impired synthesis were collected for cretinine clernce nd microlumin nd/or secretion of RBP4. One of serious microvsculr mesurement. The volume of the collected urine ws compliction in type dietic ptients ws nephropthy determined nd prt volume of urine ws centrifugted t [1]. The renl function is decresed t the eginning of 3000g for ten minutes. Prt of the urine ws used for the dietic nephropthy which chrcterized y slight immedite ssy of cretinine in urine. The rest prt glomerulr dysfunction, which is linked closely to volume of urine ws divided into liquots nd stored t elevted urinry lumin excretion in the rnge of 0 c for susequent estimtion of microlumin in urine microluminuri [13]. The impct of nephropthy on the y ELISA (NEQAS, UK) [16]. TDM ptients were plsm RBP4 in type dietic sujects is of specific clssified into two sugroups sed on their relevnce nd needs to e ddressed in the discussion on microluminuri ccording to criteri from Americn the importnce of RBP4 s n dipokine nd its role in the Dietes Assocition. pthogenesis of type dietes mellitus. We therefore investigted if the presence of incipient nephropthy Sttisticl Anlysis: The sttisticl pckge for socil might contriute to elevted levels of RBP4 in type science (SPSS) progrm version 16.0 ws used for dietic ptients. For this, we studied the comined effect nlysis. Results re reported s men ± SD. One wy of oth type dietes mellitus nd microluminuri on ANOVA ws performed for nlysis of more thn serum RBP4, s well s, we investigted reltionships vriles followed y post hoc test for detection of etween serum levels of RBP4 nd vrious metolic significnce. Simple liner correltion (Person's prmeters in Egyptin ptients with TDM correltion) ws used for quntittive dt. Qulittive dt were presented s frequencies (n) nd percentges MATERIALS AND METHODS (%). Chi-squre (x ) test ws used for comprisons etween the three groups. Comprisons of quntittive The study included (60 ptients with type dietes dt were done using the Student s t test for dt with mellitus, 8 mles nd 3 femles) were recruited from the norml distriution nd nonprmetric tests Dietic Deprtment t Ksr El-Aini Hospitl, Ciro (Mnn Whitney test) for dt not ssuming norml University, Egypt. TDM ws dignosed if the fsting distriution s in cse of microluminuri. plsm glucose (FPG) ws =16 mg/dl (7.0 mm/l) nd/or the ptients were receiving tretment for TDM [14]. RESULTS TDM ptients were on diet nd metformin or sulfonylure. Ptients with known liver disese nd those Demogrphic dt nd clinicl prmeters of studies currently treted with Thizolidinediones were excluded groups (men ± SD) re shown in Tle 1. TDM ptients from study. Helthy dults mtched for ge nd BMI were hd significntly higher men vlues of systolic lood chosen s control group, which included 0 sujects, 7 pressure, distolic lood pressure, fsting lood sugr, h mles nd 13 femles. Informed consent ws otined post prndil lood sugr, triglycerides nd HA1c from ll prticipnts efore the study. Detiled history, compred with the control sujects. Men urine cretinine physicl exmintion nd lortory testing were crried nd cretinine clernce levels were significntly lower in out for ll prticipnts. BMI were clculted for ech TDM ptients. Men vlues of serum RBP-4 levels were prticipnt y weight in kg divided y the squre of the significntly higher in TDM ptients compred with the height in meter. Ten ml of venous lood ws collected controls, lso men vlues of serum RBP-4 levels in mles 40

3 Glol J. Biotech. & Biochem., 10 (1): 39-46, 015 Tle 1: Demogrphic dt nd clinicl prmeters of studies groups. Dietics (n = 60) Control (n = 0) Vriles Men ± SD Men ± SD P-vlue Age (yers) 51.3 ± ± BMI (kg/m ) 31 ± ± Systolic Blood pressure (mmhg) ± ± * Distolic Blood pressure (mmhg) 85.8 ± ± * ) G.F.R. (ml/min/1.73cm ± ± Cholesterol (mg/dl) ± ± T.G. (mg/dl) ± ± * HDL (mg/dl) 4.3 ± ± LDL (mg/dl) ± ± Urine volume (ml) ± ± Urine Cretinine (mg/dl) 75.9 ± ± * Cretinine clernce (m/min) 8.4 ± ± * F.B.S (mg/dl) ± ± 14.5 <0.001* h.b.s (mg/dl) 7. ± ± 1.5 <0.001* Ure (mg/dl) 30.6 ± ± Cretinine (mg/dl) 0.91 ± ± Uric cid (mg/dl) 5.06 ± ± HA1c % 7.57 ± ± * RBP4 (ng/ml) 53. ± ± * RBP4 (ng/ml) mle 57.18± ± * femle 49.76± ± * *: Significnt t P= 0.05, BMI; ody mss index, G.F.R.; Glomerulr filtrtion rte, T.G.; triglyceride, HDL; High density lipoprotein, LDL; Low density lipoprotein, F.B.S; fst lood sugr, h.b.s; post prndil lood sugr, HA1c; Glycted hemogloin, RBP4; retinol inding protein. Tle : Comprisons etween T DM ptients nd controls ccording to luminuri sttus (Normoluminuri nd Microluminuri). Dietics (n = 60) Normoluminuri (n = 49) Microluminuri (n = 11) Control (n = 0) Vriles Men ± SD Men ± SD Men ± SD P-vlue Age (yers) 51.9 ± ± ± BMI (kg/m ) 31. ± ± ± Systolic lood pressure (mmhg) 13.8 ± ± 7 11 ± * Distolic lood pressure (mmhg) 86.1 ± ± ± * G.F.R. (ml/min/1.73cm ) 685 ± 39.5 c ± ± * Cholesterol (mg/dl) 00 ± ± ± * T.G. (mg/dl) ± ± ± HDL (mg/dl) 4. ± ± ± LDL (mg/dl) 11 ± ± ± Urine volume (ml) 1454 ± ± ± Urine cretinine (mg/dl) 75.7 ± ± ± Cretinine clernce (m/min) 85.6 ± ± ± * F.B.S (mg/dl) ± ± ± 14.5 <0.001* h.b.s (mg/dl) 67.1 ± ± ± 1.5 <0.001* Ure (mg/dl) 9.6 ± ± ± Microluminuri ( g/ml) 8. ± ± ± 4 <0.001* Cretinine (mg/dl) 0.87 ± ± ± Uric cid (mg/dl) 5.13 ± ± ± HA1c % 7.64± ± ± * RBP4 (ng/dl) ±6.46 c ± ± * *: Significnt t P = 0.05, Mens with different letters re sttisticlly significntly different 41

4 Tle 3: Results of correltion etween RBP4 nd different vriles in dietics nd control groups Dietic ptients (n = 60) Vriles Correltion coefficient (r) P-vlue Age (yers) * Gender * BMI (kg/m ) Systolic lood pressure (mmhg) Distolic lood pressure (mmhg) G.F.R. (ml/min/1.73cm ) Glol J. Biotech. & Biochem., 10 (1): 39-46, 015 GFR, cholesterol, triglyceride, HDL, LDL, ure, cretinine, Cholesterol (mg/dl) cretinine clernce nd uric cid. T.G. (mg/dl) HDL (mg/dl) LDL (mg/dl) Fsting lood glucose (mg/dl) * h. lood glucose (mg/dl) * Cretinine clernce (mg/dl) Ure (mg/dl) Cretinine (mg/dl) Uric cid (mg/dl) HA1c % * *: Significnt t P = 0.05, scored s 1 for mle nd for femle in the nlysis. were significntly higher in TDM ptients compred with mle control group, s well s, in femles TDM ptients compred with femle control group. Moreover, men vlues of serum RBP-4 in mles were significntly higher thn femles in control nd TDM ptients. No significnt differences were found etween TDM nd controls in ge, BMI, G.F.R., cholesterol, ure, cretinine nd uric cid. Dietic ptients were sudivided into sugroups ccording to their luminuri levels s normoluminuric or mcroluminuric. The clinicl vriles of the normoluminuric, mcroluminuric nd control sujects hve een displyed in Tle. No significnt differences etween three groups in ge, BMI, cholesterol, ure, cretinine nd uric cid. The serum RBP4 levels in micromcroluminuric ptients were significntly higher thn in normoluminuric ptients nd the control group, while systolic lood pressure, distolic lood pressure, fsting lood sugr, h post prndil lood sugr nd HA1c in normoluminuric nd micromcroluminuric ptients were significntly higher thn in the control group. Men G.F.R in control group showed the sttisticlly significnt highest. This ws followed y normoluminuric group, while microluminuric group showed the sttisticlly significnt lowest men G.F.R. There ws no sttisticlly significnt difference etween men cretinine clernce in normoluminuri nd control groups which showed the sttisticlly significntly highest vlues. Microluminuri group showed the sttisticlly significnt lowest men cretinine clernce. Correltion etween serum RBP4 nd other clinicl chrcteristics hve een displyed in Tle 3. In TDM ptients, serum concentrtion of RBP4 ws positively correlted with ge, fsting lood sugr, h post prndil lood sugr nd HA1c nd inversely correlted with femle gender. There were no significnt correltions etween RBP4 nd BMI, DISCUSSION The numer nd diversity of identified dipokines re growing rpidly [17]; nd understnding of the diverse effects of distinct dipokines s well s the interply etween these ioctive meditors is still incomplete [18] nd, if fully elucidted, would provide much etter understnding for the moleculr sis of TDM. Type DM is metolic disorder resulting from the comintion of resistnce to insulin ction, deficiency of insulin secretion nd excessive or inpproprite glucgon secretion [19]. TDM is ssocited with some disese such s hypertension nd crdiovsculr disese nd is chrcterized y trget-tissue resistnce to insulin [0]. The present study showed tht serum RBP4 levels were significntly elevted in dietic ptients in comprison with control sujects. Our results greed with different studies [1-8] tht demonstrted elevted serum RBP4 levels in type dietic sujects. Severl mechnisms linking RBP4 to insulin resistnce nd type dietes hve een investigted. To our knowledge, the RBP-4 gene is locted on chromosome 10 (10q3-q4) in humns in region tht contins t lest 1 interesting gene, hexokinse 1, the gene encoding key enzyme in the initil step of glucose metolism [9]. Furthermore, incresed serum RBP-4 levels re known to stimulte heptic gluconeogenesis through stimultion of phosphoenolpyruvte croxykinse nd the ttenuted insulin signling in skeletl muscle [30]. Insulin signling in primry humn dipocytes ws ffected y RBP4 through locking the insulin-stimulted phosphoryltion of insulin receptor sustrte-1 t serine in position 307 [31]. The link etween RBP4 nd type TDM could lso e medited through impired insulin secretion, insulin levels were not mesured in the present study. However, Nehl et l. [] found circulting RBP4 concentrtion ws negtively ssocited with insulin secretion in Egyptin TDM. In fct, it is well known tht retinolis 4

5 Glol J. Biotech. & Biochem., 10 (1): 39-46, 015 pthophysiologiclly linked to â-cell function. RBP-4 [40] found tht there were positive correltions etween circultes in serum, forming complex with trnsthyretin. the serum RBP4 concentrtion nd oth systolic nd Borch et l. [3] found tht trnsthyretin constitutes distolic lood pressures. These uthors used multiple functionl component in pncretic â-cell stimulus- liner regression nlysis which showed tht serum RBP4 secretion coupling. Trnsthyretin locked RBP receptors concentrtion ws independently ssocited with systolic which prevent inding of RPB to its receptor. Thus, lood pressure. This ws in ccordnce with the findings incresed serum RBP4 my prevents trnsthyretin from of others, who speculted tht RBP4-medited cellulr exerting its â-cell stimulus-secretion effects [33]. uptke of retinol ctivtes inflmmtion nd induces The present study showed tht mle ptients with rteriosclerosis, resulting in elevted lood pressure [34]. type dietes mellitus hd significntly higher serum In this study, whether the presence of microluminuri RBP4 concentrtion thn femles, s well s, in control s n erly mrker of dietic nephropthy is ssocited group. These findings re in consistent with the findings with chnges in the concentrtions of serum RBP4. Our of Cho et l. [6], Chi et l. [34], Ji et l. [35] nd results showed tht the RBP4 levels of ptients who hd Kim et l. [36] this difference cn e prtly explined y microluminuri were significntly higher thn the vritions etween-gender in ody ft nd sex hormone normoluminuric dietic sujects nd controls levels. Recently, Kos et l. [37] found higher RBP4 mrna consistent with the findings of Ril et l. [41] nd expression in dipose tissue in femles when compred Li et l. [4]. These results imply tht excretion or with mles; however, RBP4 mrna expression ws not degrdtion of RBP4, together with other dipocytokines, reflected in the circulting levels. Mny studies hve my hve een impired from the erly stges of dietic declred the reltionship etween the incresed nephropthy Moreover there were significnt positive circulting RBP4 nd incresed fsting plsm glucose correltion etween microluminuri nd levels of RBP4, levels [38,39], in light of our result, we found positive so these incresed in the levels of RBP4 might e significnt correltion etween RBP4 nd fsting lood consequence of incipient dietic nephropthy s glucose s well s with h post prndil lood glucose mesured y microluminuri. In this study we found concentrtions which might suggest tht the over- tht GFR ws different etween the groups indicting tht secretion of RBP4 my negtively ffect B-cell function the presence of microluminuri ws relted to chnges nd this is in greement with Broch et l. [3], who in the GFR. Might e to the renl clernce of lowconcluded tht RBP4 could e one signl from insulin- moleculr weight proteins is close to the GFR [43], it ws resistnt tissues tht -cell secretion nd this impcts on found n inverse correltion etween RBP4 levels nd mechnism could e ehind the ssocition etween GFR ut ws not significnt; it is therefore, unlikely tht incresed circulting RBP4 nd type dietes. However, chnges in the GFR re responsile for the elevted RBP4 Cho et l. [6] reported no ssocition etween circulting levels. Ril et l. [41] showed tht plsm of type RBP4, glucose concentrtions nd B-cell function [8]. dietic sujects hd the lower molr rtios of retinol to Dt regrding the reltionships etween RBP4 levels nd RBP4 nd were the lowest in ptients with BMI re inconclusive [4, ] nd in line with our results, microluminuri, in dditionlly they found the higher no correltions were found etween the serum RBP4 level percentge of circulting po-rbp4. This might e due to nd BMI. This might due to the study popultion which dmging effect of filtered protein on the proximl tuules comprised ptients with type dietes mellitus, with which decresed renl uptke nd ctolism of po-rbp4 nrrow BMI rnge nd poor islet function nd received [44], ecuse po-rbp4 hs een considered s glucose lowering tretments. In our ptient group, no physiologicl positive-feedck signl from peripherl correltions were found etween the RBP4 nd lipid tissues for the heptic relese of the RBP4 complex [45]. prmeters, which my e due to tht most of our ptients Therefore, RBP4 elevtes in serum of type dietic treted with ntilipidemic gents which msked the rel sujects with miocroluminuri s result of increses reltion etween RBP4 nd lipid prmeters. This comes of po-rbp4 which seems to e plusile mechnism. in line with the finding of Aky et l. [4]. However, Mski et l. [46] found tht RBP4 levels were The present study showed tht oth systolic nd not chnged in ptients with microluminuri compred distolic lood pressures were significntly higher in with normoluminuri. In ddition, Cre et l. [15] TDM ptients nd correlted positively with RBP4, ut reported tht RBP4 ws relted to cretinine nd GFR ut this correltion ws not significnt. Recently, Wng et l. the presence of microluminuri ws not ssocited with 43

6 Glol J. Biotech. & Biochem., 10 (1): 39-46, 015 RBP4 levels in type dietic ptients. These dt 3. Philomen Alptt, Fngjin Guo, Susn M. suggests tht RBP4 does not chnge in the erly stge of dietic nephropthy ut deteriortion of kidney function contriutes to the elevted RBP4 concentrtions in dietic nephropthy. Komnetsky, et l Liver Retinol Trnsporter nd Receptor for Serum Retinol-inding Protein (RBP4). The Journl of Biologicl Chemistry, 88: Severl explntions could e postulted to explin 4. Aky, N. Muslu, E. Ny, O. Ozhn nd the controversy of different studies: different ethnic popultions in the studies, RBP4 genetic vrition, different methods of mesurement of RBP4, sex-specific dimorphism of RBP4, the chrcteristics of the ptients, or the tretment used. Different ssys hve een used to mesure RBP4 levels nd this could ccount for the vried results reported y different lortories. A recent study 5. A. Kiykim, 010. Serum retinol inding protein 4 level is relted with renl functions in type dietes. J. Endocrinol. Invest., 33: 75-79, 010 DOI: /704. Sun, H. nd Riki Kwguchi, 011. The Memrne Receptor for Plsm Retinol Binding Protein, New Type of Cell-Surfce Receptor. Int. Rev Cell reported strong correltion etween RBP4 mesured y Mol Biol., 88: doi: /b western lot nd y ELISA, ut neither method ws le to detect difference in plsm RBP4 concentrtions 6. Xu, S. nd P. Venge Lipoclins s iochemicl etween insulin sensitive nd insulin-resistnt individuls mrkers of disese. Biochim. Biophys. Act, [38]. It ws suggested tht sex-specific dimorphisms in 148: circulting levels of dipokines cn e relted to direct 7. Alptt, P., F. Guo, S.M. Komnetsky, S. Wng, effects of sex hormones on dipocyte expression nd J. Ci, et l Liver retinol trnsporter nd secretion. In cse of RBP4, this possile mechnism is not receptor for serum retinol-inding protein supported y the fct tht serum RBP4 levels re similr (RBP4). J. Biol. Chem., 88: doi: in puertl nd prepuertl sujects tht significntly /jc.m differ in levels of circulting sex hormones [47]. A 8. Jnke, J., S. Engeli, M. Boschmnn, F. Adms, possile direct role of gondotropins on the expression of J. Bohnke, et l Retinol-inding protein 4 in RBP4 is lso proposed, s circulting RBP4 levels re humn oesity. Dietes 55: doi: higher in post menopusl compred with premenopusl women nd in women older thn 50 yers when compred with those younger thn 50 yers [48]. In conclusion, our results showed tht concentrtions of serum RBP4 were incresed in type dietic ptients nd were relted to the presence of incipient nephropthy mesured y microluminuri. Dietic nephropthy is n dditionl fctor tht might e responsile for elevted serum RBP4 in type dietes mellitus nd should e considered when discussed RBP-4 in TDM. REFERENCES 1. Friee, D., M. Neef, S. Ers, K. Dittrich, J. Krtzsch, et l Retinol inding protein 4 (RBP4) is primrily ssocited with dipose tissue mss in children. Int. J. Peditr. Oes., 6: e Vergès, Boris Guiu, Jen Pierre Cercueil, et l. 01. Retinol-Binding Protein 4 Is n Independent Fctor Associted With Triglycerides nd Determinnt of Very Low-Density Lipoprotein-Apolipoprotein B100 Ctolism in Type Dietes Mellitus. Arterioscler Throm. Vsc. Biol., 3: /d Gomez-Amrosi, J., A. Rodriguez, V. Ctln, B. Rmirez, C. Silv, et l Serum retinol-inding protein 4 is not incresed in oesity or oesityssocited type dietes mellitus, ut is reduced fter relevnt reductions in ody ft following gstric ypss. Clin. Endocrinol (Oxf) 69: doi: /j x 10. Oerch, A., M. von Bergen, S. Bluher, S. Lehmnn nd H. Till, 01. Comined serum proteomic nd metonomic profiling fter lproscopic sleeve gstrectomy in children nd dolescents. J. Lproendosc Adv. Surg. Tech. A : doi: /lp Oerch, A., M. Bluher, H. Wirth, H. Till, P. Kovcs, et l Comined proteomic nd metolomic profiling of serum revels ssocition of the complement system with oesity nd identifies novel mrkers of ody ft mss chnges. J Proteome Res 10: doi: /pr Gilert, R.E. nd D.J. Kelly Nephropthy in type dietes: current therpeutic strtegies. Nephrology, 6:

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