**15. Summary**

*Innovations in Assisted Reproduction Technology*

**chromatin**

abnormalities of head.

**reproductive outcome**

DNA. PXRX4 is necessary for condensation in testes where as GPRX4 is specifically in epididymis. Hydrogen peroxide acts as signalling molecule and causes phosphorylation of tyrosine molecules in the receptor, necessary for proliferation of sperm cells [31]. Abnormal signalling by hydrogen peroxide leads to sperm cancer which can be avoided by reduction of H2O2 by enzymes like SOD and catalase. Totally GPRX4 and

PXRX4 is necessary for nuclear stability, condensation and spermiogenesis.

**13. Factors responsible for condensation and decondensation of** 

**14. Assisted reproductive technologies required for success of** 

*Percentage of cells with DNA fragmentation using different techniques of assessment.*

ICSI and IVF are the techniques used in assisted reproductive technology, in which ICSI resulted in more percentage of PCC (pre mature condensation of

Zinc is well known for maintenance of membrane stability and found to be present in seminal plasma. It is decreased during penetration of sperm in to the female reproductive tract and decrease of zinc causes premature decondensation of chromatin as it destabilises the sperm plasma membrane. Albumin also binds to zinc and accelerates decondensation. In humans heparin is involved in decondensation of chromatin. Zinc also binds to free thiols and increases stability of chromatin, necessary for reducing disulfide bonds and accelerating the reaction (**Figure 4**). Few of the recent techniques used for measurement of DNA condensation and decondensation include using of TPM motions and energy. Condensation of DNA leads to decrease in length as protamines are organised as toroids. Where as decondensed chromatin is more in length as protamines are replaced by histones. Differences in motions of the DNA attached to the coverslip is captured and ultimately the difference in energy. Positive relation is seen between the persons with premature decondensation in DNA and infertility and DNA damage based on the studies in human subjects. Sperm fluorescent in situ hybridisation is other technique used to assess the relation between sperm DNA [32] condensation and

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**Figure 4.**

Condensation of sperm genome was necessary for maintaining genome integrity by transition of histones by transition proteins which in turn by protamines. These proteins undergo some of PTM namely phosphorylation, Acetylation, poly ADP ribosylation and methylation. Further stability in interaction between DNA and protamine involves addition of disulfide bonds to form interlinking protamines. Dihydrotestosterone acts as hydrogen donor and acceptor in testes and necessary for maturation of sperms. Zinc acts as stabiliser of Genome through its interaction with protamines and toxicity due to metals responsible for male infertility [36] is due to interaction of these metal ions with protamines. So, safe ART is required to maintain genome integrity in offspring.

### **16. Metosartan acts as genotoxic agent of testes**

Metosartan induces endometrial carcinoma in testes and causes changes in chromatin dynamics and causes prematurity in sperms. It causes competitive and non competitive inhibition of RNase present in male Wistar rats. It also decreases the sperm count, motility and induces abnormalities in sperm structure. It also causes apoptosis in both testes and sperm by increasing the permeability of mitochondria.
