Homocysteine, Vitamin B6, and Lipid in Cardiovascular Disease by SNz207M

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									Homocysteine, Vitamin B6,
and Lipid in Cardiovascular
          Disease

  Journal : Nutrition. 18:595-598,2002.
  Speaker: Shan-Yu Ho
  Date : 2003.4.10


                  Shan-Yu                 1
          Introduction
Homocysteine
sulfur-containing amino acid
an intermediate product of methionine metabolism
three forms in plasma/serum


                  sulfuration




                    Shan-Yu                   2
            Homocysteine metabolism
                                Methionine
 Methyl
             5-adenosyl                               【remethylation】
 acceptor
             methionine
                                                    Methyl transferase
Methylated
             5-adnosyl
acceptor     homocysteine
                                Homocysteine

                 Cystathionine synthase     Vitamin B6
                                  Cystahionine              【trans-sulfuration】
                 Cystathionine synthase     Vitamin B6

                                      Cysteine              Circulation. 1999;99:178-182.
                                          Shan-Yu                               3
Increase homocysteine concentration
                   Methionine
                                       Methyl transferase
                                        【Genetic deficiency】

                   Homocysteine

    Cystathionine synthase     Vitamin B6           【nutritional deficiencies,
                                                      life style , drugs ,
                     Cystahionine                      some diseases 】
    Cystathionine synthase     Vitamin B6

                         Cysteine
                             Shan-Yu                                    4
                                       Journal of Nephrology. 15(4):414-21, 2002
Vitamin B6
water-soluble vitamin
three major chemical forms:
pyridoxine, pyridoxal, pyridoxamine
wide variety of functions in your body
       【pyridoxal   phosphate;PLP】

sources(highest):brewers yeast, carrots, chicken, eggs,
                    fish, brown rice, and whole grains.
deficient signs :dermatitis, glossitis, depression,
confusion.
                       Shan-Yu                            5
Studies
Plasma homocysteine levels is an independent
risk factor for cardiovascular disease.
          (Kuller., 1998;Hankey et al., 1999;Keebler et al, 2002)

Plasma homocysteine levels is normally < or =
12 micromol/L, but when it elevated has many
deleterious cardiovascular effects.
                                            (Warren., 2002 )
High homocysteine levels in plasma promotes
oxidant injury to the vascular endothelium, and
it damage leads to platelet activation and
thrombus formation . (Loscalzo et al., 1998;Maxwal., 20006)
                    Shan-Yu
Studies
High plasma homocysteine levels is due to
genetic defects in the enzymes that control
homocysteine metabolism, and nutritional
deficienciency in vitamin B6.
                              (Blanco et al., 2001)

Vitamin B6 deficiency is an increase in
homocysteine plasma concentration and is
associated to an increment in cardiovascular
diseases.
                              (Tottes et al., 2001 )
                   Shan-Yu                             7
         Purpose

vitamin B6, lipids, Age, BMI, WHR

                   ?
     plasma homocysteine levels


                    ?
       Cardiovascular disease
              Shan-Yu               8
               Result
  Subjects


 Variables        CVD            Healthy
                (n=248)         (n=114)
    Age                    52± 20y

BMI(kg / m2)    24.9 ±0.3       22.0 ±0.4

   WHR         0.85 ±0.0051 0.82 ±0.0083

CVD:cardiovascular diaease
                 Shan-Yu                    9
    Plasma homcysteine levels ? Cardiovascular disease


A
        Variables       CVD          Healthy
                      (n=248)       (n=114)
        Hcy(μM)       12.2 ±0.3      8.5 ±0.3

        Cys(μM)       207.7 ±3.6    185.9 ±4.4

      Cys-Gly(μM)     30.9±1.4      28.5 ±0.9


                        Shan-Yu                   10
B
    4 μM




       Shan-Yu   11
Patients with cardiovascular disease
had higher homocystenine levels in
plasma than healthyl controls.




               Shan-Yu                 12
    Plasma vitamin B6 levels   ? Cardiovascular disease

A                                  B




     CVD                               Male with CVD
     Healthy             Shan-Yu       Female with CVD   13
The plasma vitamin B6 levels of
patient with cardiovascular disease
was lower than healthyl controls.




               Shan-Yu                14
Plasma lipid levels   ? Cardiovascular disease




                 CVD              Healthy
                        Shan-Yu                  15
Patient with cardiovascular disease
had lower HDL levels than healthy
controls.




               Shan-Yu                16
    vitamin B6, lipids,        Plasma homcysteine levels
                        ?
    Age, BMI, WHR              in cardiovascular disease



 Correlation   Age BMI WHR Vitamin B6 Lipids
   CVD
Homocysteine   +     +             +      -          -




                         Shan-Yu                      17
Patient with CVD had high
homocysteine levels was influenced by
age, BMI, WHR, and not by plasma
vitamin B6 and lipid profiles.




              Shan-Yu                   18
               Discussion
The elevated homocysteine levels appeared to be a
risk factor for CVD. (Genest et al.,1999;Kullo et al.2000)

Vitamin B6 deficiency is an important factor for
CVD.                               (Smith et al.,1995)
The female with CVD had lower homocysteime
levels than male patient , which may be caused by
sex hormone on the Hcy metabolism.
                                         (Hek et al.,2000)
The patient with CVD had higher BMI and WHR
than healthy controls, and WHR had stronger
positive association with CVD than BMI.
                       Shan-Yu                        19
                                       (Folsom et al.,1998)
            Conclusion


Plasma vitamin B6 status and lipids profile
 are homocysteine-independent factors of
         cardiovascular disease.




                  Shan-Yu              20
Thank you for your
    attention.



   Shan-Yu       21

								
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