Vitamin DAdipocytokines

….and GDM pregnancies

Objectives: To review the role for Vit D as an insulin-

sensitizing hormone, with particular reference to GDM pregnancy

To review some of the roles for adipocytokines in insulin resistance and GDM pregnancy

To review our local experience with Vit D/adipocytokines in GDM women and their neonates

But first….back to med school for a moment

Vitamin D: a few reminders

Ergocalciferol (D2): provitamin form

Cholecalciferol (D3): inactivated, unhydroxylated form

25(OH) Vit D3: this from is the least variable, and considered best measure of sufficiency. Therefore, most common form measured.

1, 25(OH) Vit D3: this form is variable. Measured in odd rare conditions such as Vit D resistant rickets

Vitamin D: a few reminders

Ergocalciferol (D2): provitamin form

Cholecalciferol (D3): inactivated, unhydroxylated form

25(OH) Vit D3: this form is the least variable, and considered best measure of sufficiency. Therefore, most common form measured. This is the form that will appear in this talk as VitD

1, 25(OH) Vit D3: this form is variable. Measured in odd rare conditions such as Vit D resistant rickets

Vitamin D: recent oddities We usually think of Vit D as promoting bone

health The last few decades have illustrated that Vit

D has hormone properties

structural similarities with testosterone, steroids, cholesterol

….cholecalciferol

…….cholesterol

Vit D and GDM: what do we know? Vit D deficiency suspected to be a risk factor

for glucose intolerance

For instance: 54 GDM, 39 IGT; 11 controls, matched for age,

BMI, pregnancy week 24-28 [NB: Iranian study]

Soheilykhah Nutr Clin Pract 2012. 25. 524

CONCLUSIONS:

83% GDM and IGT women had VitD <20ng/ml vs 71.2% Controls (p=0.03)

Lowest VitD levels were in GDM women compared to Controls

Does Vit D status predict GDM risk? 953 pregnant women in USA Nested case/control study VitD level taken at 16 weeks gestation 57 women developed GDM

Zhang Plos One 2008.3.e3753

CONCLUSIONS

VitD at 16 wks in women developing GDM: 24.2 ng/ml

vs Controls: 30.1 ng/ml (p<0.001)

[Difference remained significant after adjusting for weight, age, race, family history of DM, prepreg BMI]

Does VitD predict adverse preg outcomes? Meta-analysis up to Oct 2012 24 studies fit criteria (Vitamin

D/status/deficiency/insufficiency/pregnancy)

Outcome: women with VitD <50 nm/l: OR 2.09 risk pre-eclampsia (CI: 1.5-2.9) OR 1.38 risk GDM (1.12-1.7) OR 1.57 risk preterm birth (1.08-2.31) OR 1.52 risk SGA (1.08-2.15)

Wei .Mat-Fetal Medicine 2013.26.889

What about interventional studies?

………..wait……………………

What links VitD and insulin resistance?

1. No one really knows

BUT

2. Perhaps: through inflammation: VitD can be shown to be associated with anti-

inflammatory properties; and insulin resistant states are also pro-inflammatory

states inflammationendothelial dysfunctionpre-eclampsia inflammationimmune modulation (IL-1 and IL-6 in

particular)

Links between VitD and insulin resistance

3. Perhaps: VitD receptors are present in the placenta and

fetal tissues VitD regulates genes involved in trophoblast

invasion/angiogenesis

Links between VitD and insulin resistance

4. Perhaps:

pancreatic beta cells have VitD receptors may regulate insulin secretion

Vit D stimulates insulin receptor expressionpromotes insulin sensitivity

VitD and inflammatory markers So:

holding onto VitD considerations

but switching over to thinking about adipocytokines

What are Adipocytokines Proteins produced by adipose cells

[note: adipose is not just unwanted insulation, but rather a large endocrine organ]

Many, many, many known and still unknown associations and effects

AdipocytokinesYou know some of these already:

leptin adiponectin TNF-α interleukins resistin

…etc….

Just a few metabolic associations of adipokines

Low adiponectin levels have been associated with an increased incidence of Type 2 DM

Adiponectin increased insulin sensitivity, fatty acid oxidation and reduces liver glucose production

Leptin reflects total body adipose mass Resistin levels increase with fat mass and

correlate with insulin resistance TNFα and IL-6 increased in obesity and are

linked to insulin resistance and type 2 DM

Functions of Adipokines?Endocrine; paracrine; autocrine roles in:

hemostasis lipids metabolism atherosclerosis BP regulation insulin sensitivity angiogenesis immunity inflammation

Miehle. Clin Endocrinology 2012.76.2

Adipocytokines and GDM

TNF-α correlates with insulin resistance in pregnancy TNF-α is released from maternal side of placenta

Leptin rises during pregnancy and falls after delivery Leptin correlates with insulin resistance in pregnancy

Adiponectin levels are lower in GDM than control preg women

Lacroix. Curr Diab Rep 2013. 13. 238

For instance:Normal Preg GDM Pre-eclampsia

LEPTIN Rises, peak at 28 wks

Increased Increased

ADIPONECTIN Declines thru out pregnancy

Decreased Increased

RESISTIN Higher than nonprgt

Increased Increased

VISFATIN Peaks 19-26 weeks then drops

Increased Increased

..So, cooking up a study in London ON

INTERESTING UNKNOWNS:

What are VitD levels in offspring of GDM pregnancies?

What are the profiles of adipocytokines in GDM women AND their offspring?

Are maternal and neonatal VitD levels correlated? Are maternal and neonatal adipokine levels

correlated? Do corralations exist between VitD and

inflammatory adiokines (maternal and neonatal)?

…..we had the following building blocks…

LUCK

Kelly Summers

’ adipokine

assay

GDM wome

n

PSI grant

Maternal, umbilical arterial and umbilical venous 25 hydroxyvitamin D and adipocytokine concentrations in pregnancies with and without gestational diabetes

R McManus, K Summers, B DeVrijer, N Cohen, A Thompson, I Giroux Clinical Endocrinology 2014; 80:635-641.

Methods Case control GDM diagnosed before clinic referral no recruitment during Nov-Mar months GDM and Controls recruited at 31 weeks Did 48 hour dietary and supplement recall

[before GDM saw RD]

Methods Maternal blood taken/spun/frozen at 31 weeks

for

Ca Phosphate BG CRP PTH Adipocytokines (adiponectin, resistin, PAI-1, IL-

6; Il-8, leptin, TNFα, MCP-1)

Methods On day of delivery:

Neonatal umbilical artery and umbilical vein bloods were taken for DR staff for:

Ca Phosphate BG CRP PTH Adipocytokines (adiponectin, resistin, PAI-1, IL-

6; Il-8, leptin, TNFα, MCP-1)

….do you want to guess?

Umbilical artery flows:

Umbilical vein flows:

So

umbilical arterial blood would reflect fetal chemistry

umbilical vein blood would reflect maternal AND placental chemistry

DemographicsMaternal age pre-pregnancy weight maternal weight at time of blood takingInfant birth weight infant gestational age apgar scores duration of hospital stay/complications

A few stats

Sample size of 24 X2=48 would allow for detecting a 30 nm/l difference between [VitD] in GDM women vs C

Results 73 women 36 GDM; 37 C Matched for week of gestation; present

weight; pre-preg weight; maternal VitD intake

MATERNAL

CHARACTERISTICS

AND BIOCHEMISTRY

CONTROL GDM p

N 37 36  

Age (yrs) 30.2±4.1 31.6±5.0 0.19

Weeks Gestation 31.4±3.6 31.6±2.9 0.84

Current Weight (kg) 85.8±21.3 89.1±16.0 0.47

Pre-pregnancy

Weight (kg)

74.4±18.9 77.7±17.4 0.44

Pre-pregnancy BMI

(kg/m2)

27.2±7.2 28.7±5.5 0.34

Maternal Vitamin D

Intake (ug/day)

14.4±6.4 15.8±2.9 0.44‡

MATERNAL

CHARACTERIST

ICS AND

BIOCHEMISTRY

CONTROL GDM p

25(OH)D (nm/L) [range] 93.2±19.2 [55-135] 77.3±24.3 [33-128] 0.009

PTH (pm/L) 4.33±16.57 1.78±1.10 0.732†

Calcium (mm/L) 2.20±0.13 2.20±0.09 0.898

Phosphate (mm/L) 1.06±0.18 1.04±0.17 0.519

GLUCOSE (MM/L) 4.68±0.89 5.46±1.29 0.008

Alkaline Phosphatase (u/L) 82.2±27.1 89.5±18.8 0.234

CRP (mg/L) 6.03±4.99 6.00±5.36 0.983

ADIPONECTIN (ΜG/ML) 34.1±20.3 17.5±11.8 <0.001†

RESISTIN (NG/ML) 31.9±12.1 25.4±9.1 0.045

PAI-1 (NG/ML) 21.0±12.6 13.9±10.0 0.038

IL-6 (pg/ml) 1.93±1.32 1.76±1.00 0.627

IL-8 (pg/ml) 2.39±0.98 2.25±1.92 0.185†

Leptin (ng/ml) 41.2±33.7 40.1±26.4 0.899

TNF-α (pg/ml) 4.99±2.08 5.83±2.46 0.196

MCP-1 (pg/ml) 115.6±52.8 115.9±81.1 0.688†

DELIVERY

OUTCOMES

CONTROL GDM p

Infant Weight (g)

GESTATIONAL AGE

(weeks)

3457.8 ± 455.2

39.5±0.9

3384.6 ± 504.2

38.2±1.2

0.547

<0.001

Apgar 1 8.2 ± 1.7 8.0 ± 2.1 0.749

Apgar 2 8.8 ± 0.5 8.9 ± 0.6 0.689

Labour Duration

(hours)

8.1 ± 5.8 7.6 ± 4.0 0.891†

Placental Weight (g) 677.2 ± 169.7 746.0 ± 197.6 0.159

Post partum Stay

(hours)

46.8 ± 15.5 45.5 ± 25.4 0.353 ‡

Sex – Male (%) 19 (59) 19 (61) 0.877

Induced Labour (%) 17 (53) 20 (64) 0.359

Caesarian Section (%) 8 (22) 6 (16) 0.51

INFANT ARTERIAL

UMBILICAL

CHEMISTRY

CONTROL GDM p

25(OH)D (nm/L) 65.6±17.6 58.0±20.8 0.195

Calcium (mm/L) 2.54±0.21 2.46±0.35 0.420

Glucose (mm/L) 3.67±0.81 3.44±1.50 0.227‡

ADIPONECTIN

(ΜG/ML)

100.0±52.2 57.0±31.7 0.006

RESISTIN (NG/ML) 222.4±456.5 57.1±34.5 0.030‡

PAI-1 (NG/ML) 21.5±22.7 11.2±6.6 0.049†

IL-6 (pg/ml) 37.8±105.7 16.9±22.3 0.779†

IL-8 (pg/ml) 20.7±23.0 11.8±5.8 0.784‡

Leptin (ng/ml) 44.7±46.4 46.1±37.9 0.910

TNF-α (pg/ml) 10.7±2.1 11.7±3.0 0.209

MCP-1 (pg/ml) 690.6±552.6 574.8±275.4 0.608†

 

INFANT VENOUS

UMBILICAL CHEMISTRY

CONTROL GDM p

25(OH)D (nm/L) 64.8±11.5 66.3±19.5 0.952‡

Calcium (mm/L) 2.62±0.25 2.50±0.18 0.086

Glucose (mm/L) 3.70±1.24 3.96±0.84 0.422

ADIPONECTIN (ΜG /ML) 109.9±49.5 64.0±33.7 0.004

RESISTIN (NG/ML) 237.4±529.2 47.5±17.9 <0.001‡

PAI-1 (NG/ML) 15.5±13.9 8.4±8.2 0.009†

IL-6 (pg/ml) 38.4±109.4 11.2±12.4 0.871†

IL-8 (pg/ml) 15.7±18.6 8.7±5.0 0.464‡

Leptin (ng/ml) 49.9±40.1 55.4±48.6 0.675

TNF-α (pg/ml) 10.9±2.5 11.8±2.8 0.253

MCP-1 (pg/ml) 457.4±289.7 425.0±247.9 0.690

Searching for correlations[we limited correlations to r>0.4 or r<-0.4; p<0.05]

Maternal Control VitD levels: + correlated with resistin only

Maternal GDM VitD: + correlated with PAI-1; IL-8; TNF-α

Searching for Correlations..cont Neonatal VitD levels were not correlated with

any of:

infant weight placental weight Apgar scores labour duration/hospital stay adipocytokines

Admitting our limitations

Big picture: no one knows what level of VitD is “ideal” for the non-osteomalacial actions of VitD

Our women were not as VitD deficient as in some studies so differing conclusions might occur if there was a wider range of serum levels

Our GDM women were generally only mildly hyperglycemic (ie) no one was on insulin when maternal bloods were taken: again a wider range of insulin impairement may have uncovered differing results

So…what…?#1: As expected:

GDM women had lower adiponectin than Controls

however, this finding was present despite being matched for weight and pregnancy week

lower adiponectin levels would be consistent with increased GDM maternal inflammation…but….

So what #2

GDM had lower resistin and PAI-1 levels [argues against inflammatory biochemical profile]

GDM leptin was not different from C

GDM CRP, ILs, TNFα, MCP-1 not different as well

overall, no conclusive evidence for inflammatory chemistry in GDM women

So what #3:

GDM maternal VitD lower than Controls

But:

Umbilical arterial and venous VitD showed no difference between GDM and C offspring

So what #4

Maternal GDM VitD levels were positively (not negatively as expected) correlated with some adipokines thought to be associated with inflammation (PAI-1; IL-8, TNFα)

Neonatal VitD levels did not correlate with inflammatory markers

So what #5

Neonates born to mothers with GDM also manifested lower adiponectin and resistin levels

even in umbilical arterial bloods suggesting that there are adverse adipokine

profiles present at birth

So what #6

We learned a very important life lesson:

Never ever again do a study where blood samples from babies have to be centrifuged and frozen at any time of day, night, holidays……

Just an aside

Enthusiasm for VitD as THE miracle metabolic hormone has waned

Much of what our study was built upon (remember, grant applied for <2008) tantalizing hints and correlations around VitD effects

However, interventional studies have suggested perhaps some effect attributable to VitD, although final word not yet in…..

For instance 54 women with GDM (Iran) randomized to placebo or cholecalciferol

50,000 u at study entry and day 21 fasting samples for BG and insulin taken at

study onset as well as after 6 weeks

Results:

VitD supplementation: was correlated with lower FG (-17.1±14.8 mg/dl vs -0.9±16.6 mg/dl, p<0.001) was correlated with lower serum insulin was correlated with improved QUICKI index

Asemi. Am J Clin Nutr 2013.98.1425

one more… 120 Iranian women <12 weeks of pregnancy randomized to:

200 u VitD OD; 50,000 u VitD monthly 50,000 u Vit D Q2 weeks

until delivery

measured:

FBG, insulin, Ca, VitD

before and after intervention

Results

Group C receiving 50,000 u every 2 weeks had biggest rise in VitD level

FBG dropped 2.02 mg/dl in Group C (NS) Insulin level in group C went up less than

Group A (NS) comparing all 3 groups: insulin and HOMA IR

were improved with higher doses of VitD supplementation

Soheilyhkhah Gynec Endocrinol 2013. 29. 396

..one last London connection DALI study

Vitamin D and lifestyle intervention for gestational diabetes mellitus (GDM) prevention: an European multicentre, randomized trial-study protocol

9 countries <20 weeks gestation 8 intervention arms (placebo, healthy diet,

healthy activity, Vit D combos)

DALI Vit D dose is 1600 u OD until delivery

primary outcome: gestational weight gain, fasting glucose and insulin sensitivity, OB outcomes

[biorepository blood is being stored at Lawson/David Hill]

Jelsma BMC Pregnancy Childbirth 2013. 13.124

that’s all ….